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THE 



PRACTICAL ENGINEER: 



SHOWING 



THE BEST AND MOST ECONOMICAL MODE FOR MODELING, CONSTUCTING 
AND WORKING STEAM ENGINES, WRITTEN IN A PLAIN, CON- 
CISE AND PRACTICAL STYLE, AND DESIGNED ESPE- 
CIALLY FOR PRACTICAL ENGINEERS, STEAM- 
BOAT CAPTAINS AND PILOTS. 



ILLUSTRATED WITH NUMEROUS DIAGRAMS, DRAFTS AND PLATES, 



BY JOHN WALLACE 

PRACTICAL ENGINEER. 



PITTSBUGH: 

KENNEDY & BROTHER, PRINTERS AND PUBLISHERS, THIRD STREET 
18 5 3. 



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Entered, acecording to the Act of Congress, in the year 1853, 

BY JOHN WALLACE, 

In the Clerk's Office of the District Court of the U. S., Western District of Penm 







W) 



PREFACE. 



The author presents to the public this volume on "practical engineer- 
ing," in the full confidence that such a work has long been desired, and 
is very much needed by the practical engineer, as well as those who 
have had little or no experience in this department of science, but whose 
business requires the aid of steam power. There have been many scien- 
tific works published upon the subject of steam, and various other mat- 
ters connected therewith, altogether foreign from the object sought to be 
explained ; if they were, indeed, intended to assist and instruct the prac- 
tical engineer. We venture the assertion that there are a hundred - 
things, aye, a thousand, the knowledge of which would be beneficial to 
the practical engineer, which have not been alluded to nor mentioned in 
the books hitherto published on this important subject. The reason of 
this may be attributed to the fact that men of mere theory have underta- 
ken to put forth books for the purpose of instructing practical men in 
matters which the authors have never learned, and about which they 
are totally ignorant. So far as the therory is correct, they are entitled 
to credit for its promulgation. 

But abstract theory can never meet the wants and instruct and assist 
the practical engineer in working steam engines. In other words, it is 
folly to presume that a theorist alone, can be possessed of such a correct 
and praciical knowledge of steam engines, as will meet the hearty 
response and approbation of that class of persons for whose benefit he 
publishes his treatise. It will readily be conceded then, that a work, 
in order to be useful, must issue from one who is acquainted not only 
with the theory but with practical engineering; and it must exhibit in 
every page evidence of the author's practical experience. When such 
isthe case, practical men will not only at once perceive the author's 
capability to explain and elucidate the different branches of the subject 
upon which he writes, but will be much pleased and instructed from a 
perusal of the work. Such a book is now presented. 

The author of this work had long experience in practical engineering, 
extending through many years, in various places, and with almost every 
description of engines. His sources of knowledge are therefore exten- 
sive, and the results of his information are given in the pages of this 
work in a plain, concise and practical style. He has been employed in 
constructing and working at engines of various kinds, in Pittsburgh, 
Wheeling, Cincinnati, Louisville, and New Albany, Indiana ; and was 
for some length of time a practical engineer in running the Ohio and 
Tennessee rivers. 



His knowledge of land and stationary engines is quite as extensive as 
that of any other persons in general, and he feels therefore confident of 
the utility of the present work to practical men. 

The author has had in contemplation to publish a work of a character 
corresponding to the present one, for some eight or ten years, thinking 
that the public would be benefitted from its perusal ; but hoping that its 
place would be superceded by some one of merit and usefulness, the pro- 
ject was time after time abandoned. After having perused many works 
from which engineers (himself among them) expected to derive benefit 
and information, and finding them wide off the point sought to be ob- 
tained, he was persuaded to rusurae the task of compiling a book appli- 
cable to the wants of the practical engineer. 

This volume, therefore, has been written and compiled especially for 
the practical man ; but its pages will be found both interesting and 
instructive to the engine builder. They would do well to consulc its 
pages previously to modling machinery for steam engines. It is enti- 
tled " The Practical Engineer," and should be in the hands of every 
steamboat Captain, as well as engineer. It will not only instruct him in 
many things of which he is ignorant respecting the machinery and work- 
ings of the engine, but will be of great use in enabling him to draw up 
an order for an engine, with so much clearness and accuracy as to ena- 
ble the builders to perfectly understand what is required, and upon what 
terms it can be filled. This is an important consideration, and one 
which, unfortunately, Captains have been heretofore too little acquainted 
with. It will also be found of interest and profit to the Pilot to read 
this work, as it may lead him to the discovery of danger from the work- 
ing of the engine, and put him upon cautionary guidance of the 
helm, &g. 

The second volume will be devoted exclusively to mill, factory, and 
other stationary engines. 

In conclusion, I would say to the practical engineer, engine builder, 
captain and pilot of boats, make this book your study, so far as duty 
requires, and you will find that your time has not been lost ; but, on the 
contrary, you will be possessed of such a general knowledge of steam 
engines, as you little thought of previous to its perusal,- and upon the 
strength of which you can each embark upon your respective duties with 
confidence, knowledge and a certainty of greater success. 

JOHN WALLACE. 

Pittsburgh, July 1, 1853. 



CONTENTS. 

BOILERS— Diameter of Boilers, 13 

Short Boilers, 13 

Long Boilers, 14 

Thickness of Boiler Iron, 15 

Thickness of Flue Iron, 18 

BOILER HEADS— Thickness of Boiler Heads, 20 

Single and Double Flued Boilers, 21 

Elbow Flued Boilers, 21 

Flued Boilers, 22 

Causes of Boilers Exploding and Flues Collapsing, 22 

Collapsing of Flues, 30 

Cylinder Boilers, 31 

Distance Between Boilers, 32 

How to Set Boilers, 33 

Weight of Steam to be carried, 33 

Fire Fronts and Back Plates, . .- 35 

Fire Fronts Lined, 35 

Burning out Grate-bars, 36 

Back Plates, 37 

STEAM AND STAND PIPES— Cast-iron Steam Pipes, 38 

Cast-Iron Stands connected with Copper Pipe, 40 

Wrought-Iron Steam Pipes, 40 

Wrought-Iron Supply Pipes, 41 

Different places for attaching Steam and Stand Pipes to Boilers,.. 42 

Steam taken from end of Pipe, 43 

Steam taken from center of a Steam Pipe, 44 

Steam taken from center and double Pipe, 44 

Steam taken from Steam-Drum, 44 

BRASS STOP-COCKS— Danger of Brass Stop-Cocks between the 

Boiler and the Force-Pump, 45 

Freezing of the Stop-Cocks, 46 

Blow-off Stop-Cocks on Boiler Stands, . . - 46 

Various modes of casting Cylinders, 46 

Four Lugs cast upon the Cylinder, 47 

Four Nossles cast on the Cylinders, 47 



Six Lugs cast on the Cylinder, 48 

Sub-Cylinder, 48 

Stroke of Cylinder, 49 

Bearing, thickness, and width of Slides, 50 

Length of Slides, 51 

Shoving-Head Bored out, 52 

Bolts for Shoving-Head Jaws, 52 

Length of Pitmans, 57 

Wooden Pitmans, 58 

Iron Pitmans, 59 

Placing in Wrists, 59 

Collar Wrists, as formerly used, 59 

Wrists, as now used, 60 

Wrists without Keys, 61 

PILLAR BLOCKS— Bottom Brasses in Pillar Blocks, 63 

Keys in Side Boxes, 64 

Backing in Side Boxes, 64 

Boring out Pillar Blocks, 65 

Large Collars on Shafts, » 65 

Small Collars on Shafts, 65 

CAMS— Setting the Pull-Stroke Cam, 77 

Setting the Cut-off Cam, 72 

Names of a variety of Cams, 73 

Slide-Valve Cams, 75 

Various causes of Engines laboring, _ 75 

Cleaning Furnaces, 75 

False motion in the Cam-Frame, 76 

False motion in the Cam Paws and Joints, 77 

Cams ma}» slip, 78 

Slide-Valve Seat out of order, 79 

Puppet-Balance and Cup- Valve may leak, 80 

Cylinder out of line, 80 

Cylinder out of true, 81 

Cylinder Packing , 82 

Packing screwed up too tight, 83 

Caps screwed too tight on the Journals, 83 

Cam-Rod, 84 

Steam throttled off too closely, 84 

Horrizoutal Force-Pump, 86 

Upright Force-Pumps, 88 



Upright Force-Pumps with Bored Chambers, 88 

Rules how to find the stroke of a Plunger by figures, 89 

Cold Water Pumps, 90 

Force-Pumps, 90 

Superior Force-Pumps, 91 

A Superior Force-Pump with au Air Vessel, 92 

The form of an order for a Steam Engine, 93 

GENERAL REMAKS — Single Engines, Double Engines, and 
Stern-Wheel Engines: — The advantages and disadvantages 
of one compared with the other — Stating which we consid- 
er the best, taking all things into consideration, 95 

Counter Balance, ~ 102 

Various ways of using the Counter Balance, 103 

Defect in Force-Pumps made in early years, 104 

The true piinciple to make a complete Force-Pump, 107 

How high a Valve should rise to make the opening around the 
circumference equal to the opening in the diameter of the 

Valve, 108 

How to cut the leather for a pump-box, 110 

Best kind of Valve Seats for force-pumps, 110 

Best kind of material for making Joints and Valve Seats, Ill 

Different causes for Steamboats taking fire, 113 

Different rules for squaring and lining shafts, 120 

Best method of holding Braces in water Wheels, 126 

Milner's cut-off Valve,. . 127 

Areas of Circles, from 1 to 100 pounds, 130 

To find the weight of steam carried in the Boiler, 136 

Puppet and Balance Valve Engine,. 144 

To Practical Engineers, '- 145 

The use of the table explained, 147 

Wallace's Vertical Steam Boiler, . 154 

Miscellaneous, . . . 157 



BOILERS. 



DIAMETER OE BOILERS. 

For the use of steamers in general we are not In favor 
of small boilers, — nothing less than 84 inches in diam- 
eter. This is as small as a man can properly clean 
out, and small enough for raising steam. Nor do we 
think it would be good policy to go over 4 feet in 
diameter for our high pressure engines. 40 and 42 
inch boilers are as large as they are generally made, 
but we believe large boilers make much more steam, 
in proportion to the amount of fuel used, than small 
ones. 



SHORT BOILERS, 

A great quantity of the heat is lost in using the 

short boilers, and we have frequently seen the blaze 

issuing from the tops of the chimneys of both river and 

land engines. 
2 



14 THE PRACTICAL ENGINEER, 

LONG BOILERS. 

Long boilers are now coming into general use. They 
have used them on our rivers 40 feet in length, and 
cylinder boilers have been made 42 feet long for land 
use. This, we think, is going to the opposite extreme ; 
40 feet is too long for a steamboat boiler. Such a 
boiler can hardly stand under its own weight without 
a center bearing, and under a steamboat boiler we do 
not approve of it. We believe it is too great a distance 
to carry the heat for making steam, whenever your 
boiler goes beyond that length, that it ceases to create 
steam. It only adds unnecessary weight, takes up 
unnecessary room, and acts as a condenser to cool 
what steam has already been made, and of two evils 
choose the least. It is better policy in this case, 
that the boiler be too short than too long, for several 
reasons : long boilers require much longer time to 
raise steam, and they will spring easier than if they 
were shorter, and by being too long they condense the 
steam at one end of the flue while you are making it at 
the other end of the boiler. Besides, they will not 
stand their own weight in hauling, or rolling, without 
being materially dinged, unless they are handled by 
skillful persons with the greatest care and precaution. 
The medium length of boilers is generally the best. 
Never choose either of the two opposite extremes. We 



THE PRACTICAL ENGINEER. 15 

would say, for general use, from 24 to 34 feet in length 
will be about the best length, varying the length from 
the one to the other to suit the different diameters of 
boilers and sizes of boats on which they are to go. 



THICKNESS OF BOILER IRON. 

No steamboat boiler made for high pressure engines, 
having boilers 24 inches and upwards in diameter, 
should be allowed to be put on boats less than J inch 
thick, and all boilers over 42 and up to 48 inches in 
diameter, should be made of 5-16 iron. We would 
here suggest an idea for the consideration of those 
who are ordering engines to be built, about the pro- 
priety of having four sheets or more of the boiler iron 
above the fire, 1-16 of an inch thicker than the bal- 
ance of the boiler, as that part of the boiler is the most 
exposed to the heat or action of the fire and is more 
likely to burn or bag than any other part of the boiler. 
We think it would be economy to make boilers 
in this way. In addition to this, we would suggest 
another idea to your minds for consideration, and we 
are fully satisfied on this subject that we are right. 
It is this : that the ^ast sheet of iron in the bottom of 
each of the boilers should be made of iron J of an inch 
thicker than the iron in the boiler hull. This is the 
sheet to which the boiler stand is to bo fastened to. 



16 THE PRACTICAL ENGINEER. 

The object of this sheet being thicker is, that the 
boiler will stand more firm and secure, and have a 
larger and stiffer bearing upon the body of the boiler 
than it now has upon a sheet of the usual thickness, 
bearing upon the small surface of a narrow flange out- 
side of the stand pipe. 

The sheets of iron on top of the boiler, which the 
steam pipe is fastened to, we would have the same 
way ; and all boilers fastened together with screw 
bolts should be J thicker than the boiler hull iron, be- 
cause J inch between the bolt springs. The iron is not 
sufficiently strong to be screwed up tight and hold large 
boilers together. 

We are aware that wrought iron steam and stand 
pipes are now used, and that they are riveted on to 
the boilers and hold the iron close together between 
the rivets ; but still that does not prevent the boiler 
from springing up and down, like a basket, on the 
boiler stands, owing to the great weight on such a small 
surface of thin iron. 

If you could bring your boiler stand, like a land 
engine, to rest on the boiler bead, then it might do — 
but this cannot be done. Had the plan which we now 
speak of been adopted when the cast iron steam pipes 
were in general use, the use of the extra flages inside 
the boilers under each steam pipe branch, with six 
holes in it, for the purpose of making the boiler iron 



THE PRACTICAL ENGINEER. 17 

stiff enough to be screwed up tightly, and help to stif- 
fen the iron between the bolt holes, could have been 
entirely dispensed with. This method of strengthening 
the boiler iron is frequently adopted, and We deem it 
patching up something that was not sufficiently strong 
in the first place. 

If boilers were made stiffer, as we have proposed, 
there would be less danger of the joints breaking, or 
of them leaking whenever exposed to stormy weather, 
or any ill-usage caused by the motion of the boats. 

We think that our government should not allow any 
steamboat boilers to be used of less than j- inch iron, 
of good quality and warranted. Boilers over 42 inches 
in diameter, 5-16 of an inch thick, and the extra f 
sheets we have alluded to for the boiler connections and 
the steam pipes, you may not at present be disposed 
to adopt ; but the last sheet of iron on the bottom of 
the boiler that rests upon the top of the boiler stands 
and bears up the whole weight of the boiler, should be 
made \ of an inch thicker than the boiler hull. Let 
every one who is interested in the welfare of the com- 
munity, and especially the traveling community, see- 
to it. We have no doubt but that the time will soon 
arrive when this plan will be generally adopted. 



2* 



18 THE PRACTICAL ENGINEER, 

THICKNESS OF FLUE IRON. 

The iron used for making boiler flues should be full 
as thick as the iron used for the boiler hull, for three 
reasons r 

1st. It is much easier to collapse a flue than to 
burst a boiler. 

2d. We very frequently hear of flues collapsing 
where it is stated that there was a sufficient quantity 
of water in the boilers ; and we believe it, from the 
fact they have frequently collapsed when about start- 
ing out, and also when obliged to stop for a few min- 
utes on account of business, after having started. We 
recollect once seeing a boat, below the Falls on the 
Ohio river, that had collapsed her flue, and which, we 
believe, was under way at the time the accident hap- 
pened. When we saw her she was in the middle of 
the river, and they were endeavoring to bring her to 
shore. The bow was covered with steam. 

3d. If the water gets a little low in the boiler, the 
tops of the flues becomes bare and are liable to become 
red hot ; and by being heated more on the top they 
become weaker just in proportion as they are heated, 
and under the pressure of the steam, flatten or press 
together. 

Experience and demonstration of the facts will not 
admit nor allow of any argument to prove to the con- 



THE PRACTICAL ENGINEER. 19 

trary, but that the flue iron made of the same thick- 
ness of the boiler, is weaker than the boilers, and for 
this reason they should be made proportionably thicker 
than the boiler hull. Another point requires partic- 
ular attention in the construction of flues : that they 
be exactly round, — not having any flat places, — for 
this materially destroys the strength of the flue ; and 
if any part is more likely to give way than another, 
it is that part which is out of round. 



20 THE PRACTICAL ENGINEER. 



BOILER HEADS. 



THICKNESS OF BOILER HEADS. 

Steamboat boiler heads should always be made of 
wrought iron. The time was when we almost univer- 
sally made them of cast iron. There arc two objec- 
tions to cast iron heads on steamboat boilers : they 
often break between the flues, and they are too heavy. 
Wrought iron heads for 34 inch boilers should not be 
less than J inch thick ; 36 inch boilers 9-16 ; 38 and 
40 inch boilers f thick ; 42 11-16 and up to 48 inches 
in diameter, f inch thick. Both front and back boiler 
heads should have at least two strong braces in each 
head, and large boilers more, if thought necessary. 
The back head in which the man plate goes, should 
have a large band riveted inside of the boiler head, 
around the man hole plate, to make the boiler head 
stiff so as to stand screwing up tight. Sometimes 
these heads are made of a solid sheet, and flanged for 
riveting to the boiler; others are made of gunnel iron, 
with a flat piece riveted inside. This, we believe, is the 
stiffest head of the two, but either of them are good 
enough if they are well made. 



THE PRACTICAL ENGINEER. 21 

SINGLE AND DOUBLE FLUED BOILERS. 

We are opposed to the use of single-flued boilers, 
believing it to be bad economy on the part of those who 
get them made. No doubt it is generally done with a 
view to save cost on the part of those who get them ; 
for one flue costs less than two. But the cost does 
not stop here, — and there are other things to be taken 
into consideration. There will be more opening in 
two flues than can be had in one, thereby producing 
a much better draft, and the flues being less in diam- 
eter will be much stronger ; and being lower down in 
the boiler there will be room for a sufficient quantity 
of water to cover the flues. In addition to this there 
will be more room in the boilers for holding steam? 
and more steam can be produced in a shorter time with 
two flues than can be made with one* 



ELBOW-FLU ED BOILERS. 

Formerly elbow-flued boilers were much used, but 
are now dispensed with altogether. The elbow flue 
joins the bottom of the boiler about three inches from 
its end, and by this arrangement a great deal of heat 
(which in the present boilers is lost on the back of the 
fire bed and back plates,) is applied to the raising of 
steam. The principal advantage to be gained by the use 



22 THE PRACTICAL ENGINEER. 

of elbow-flued boilers is the power they have of gener- 
ating more steam than those now in use, but this ad- 
vantage is of no practical account from the fact that 
the pressure of steam is unequal on the elbows of the 
flue ; and although they are braced up with bolts, yet 
they cannot be made sufficiently strong, but are apt to 
collapse in the elbow which is the weakest part of the 
flue. This makes it unsafe and of course unfit for use. 



FLUED BOILERS. 

Quarter circle flued boilers are quite as dangerous 
as elbow flues. They work on the same principle but 
differ a little in their construction. They take up 
about two feet less room in the length of the fire bed 
and absorb most of the heat returning into the flue ; 
but they are unsafe for high pressure engines and 
therefore unfit for use. 



CAUSES OF BOILERS EXPLODING AND 
FLUES COLLAPSING. 

The explosion of boilers and collapsing of flues pro- 
ceed from various causes, a few of which we will 
endeavor to show. First we will speak of the explo- 
sions of former years and then refer you to some of 
modern days and compare them together. In former 



THE PRACTICAL ENGINEER. 23 

times boilers were seldom made more than half the 
length of those in present use. Sixteen, eighteen, and 
tweenty feet used to be a common length for steam- 
boat boilers, and being so short they were sooner filled 
with water than the present large boilers can be, and 
also much sooner boiled dry or emptied of water by 
the blowing off of steam. As soon as the engine stop- 
ped the steam would be blowing off, carrying more or 
less of the water in the boiler with it, and consequently 
required more regular attention to the water than the 
boilers of the present day, — owing to the additional 
length. The extra length of the boilers of the present 
day allow about double the room for steam, and by 
opening the furnace doors and flue caps, there is but 
little necessity for blowing off steam, compared to that 
of former days. 

We would also state that although the long boilers 
generate more steam in the same length of time, in 
proportion to the amount of fuel used, than the short 
ones, when either of the engines are stopped, the short 
boilers will commence blowing off steam almost instant- 
ly, and that with the furnace doors and cap flues open. 
The reason of this is that the heat is much greater on 
the short, to the amount of boiler, than it is on the 
long boilers. Hence we believe that the principal 
cause of explosions in former times to have been the 
small amount of water that was carried on the top of 



24 THE PRACTICAL ENGINEER. 

the flues in the boiler. The lower gauge cock, which 
was also the water gauge, was placed at about an 1J 
or 2 inches above the top of the flues, and the upper 
cock was about 2J or 3 inches above this. Now while 
long boilers gencraly carried from five to six inches of 
water on the top of the flues and had scarcely any 
occasion to blow off steam, and if it is considered neces- 
sary at the present day to carry a greater amount of 
water than formerly for safety, this proves that the 
lower water gauge cock carried water too low for safe- 
ty, and had it been carried in short boilers in propor- 
tion as it is now carried in long ones, the lower gauge 
cocks instead of being one and a half or two inches, 
would have been 8 or 10 inches above the top of the 
flues, and this would have prevented many of the short 
boilers from blowing up, and the same amount of steam 
blown off as soon as the engine was topped, w T ould have 
made them nearly as safe as the long boilers. 

Taking all things into consideration, it is a wonder 
that explosions have not been of more frequent occur- 
rence. There was something radically wrong in the 
former construction of engines. No doubt many good 
boats have been blown up for want of doctors to keep 
up a regular supply of water during long stoppages at 
wood yards, landing passengers, &c. It was formerly 
customary to stop bGats in the channel of the river 
and send or receive passengers from the shore in a 



THE PRACTICAL ENGINEER. 25 

yawl. During these stoppages more or less steam 
would be blown off, and it was impossible to pump any 
water into the boilers until the boat could be got un- 
der way again. Sometimes, in receiving or discharg- 
ing passengers, where the width of the river would 
admit, the boat would run around in a large circle to 
keep the engines in motion for the purpose of supply- 
ing the boilers with water ; and at wood-yards, the 
wheels were unshipped for the same purpose. 

Very soon, however, single engines were succeeded 
by double, which proved of no advantage, for it was 
more difficult than ever to supply the boilers with water 
when the engine was stopped. If the boilers were 
supplied at all the water wheel must be kept in motion, 
and often the shore engine could not be run at all. 
To run the outside wheel to pump up water would 
probably take as much steam as it would require to run 
the boat, and to supply the boilers at such an expense 
would have been bad policy. This shows that there 
was something wanting in the machinery to make it 
complete. 

Not having had time to ascertain the particulars, or 
to make any inquiries whether there were any doctors 
used previous to this, we cannot, therefore, give any 
definite information on the subject. The first doctor 
we heard of was used on a small steamer called the 
Orleans, and some four years elapsed after this before 



26 THE PRACTICAL ENGINEER. 

they were deemed so important as to become general. 

It was about this time that engines were changed 
from single to double, and this plan was adopted upon 
the steamer Missouri, a large seven-boiler boat. Im- 
mediately after this the doctors came into general use, 
and are now considered indispensable, especially on 
large steamers. We can now stop our steamers when 
and where we please, and as long as may be required, 
without any fear of water from not running the en- 
gines, for the doctor is ready at all times independent 
of the main engine. 

We would here state some particulars in relation to 
the explosion of boilers. We will also mention the 
kind of boilers used and state where they exploded. 
The first was the Moselle, a small three-boiler boat, 
that exploded while putting out from Cincinnati, and 
killed about 150 persons. We were well acquainted 
with both her engineers, the principal one having 
worked at a shop in Wheeling in which we were a part- 
ner. The Moselle made use of the short boilers, and 
had no doctor. She exploded as she was about put- 
ting out, immediately after starting the engines. The 
Ben Franklin had started just ahead, and we under- 
stand the captain said he would beat her, &c. 

The Gen. Brown, a four-boiler steamer, running 
between Louisville and New Orleans, burst her boiler 
while putting out from a wood-yard, when about mak 



THE PRACTICAL ENGINEER. 27 

ing her second revolution. We were acquainted with 
both those engineers, one of whom was instantly killed. 
The other survived, but had both arms broken. The 
latter worked under the same firm while we were prin- 
cipal foreman, at New Albany, Ind. Some forty per- 
sons were killed by this explosion. We were but little 
surprised at the blowing up of this boat, as she was in 
the habit of making " brag trips" from New Orleans 
to Louisville. The Brown's boilers were short, and 
she had no doctor, and no doubt there was too much 
steam and too little water in the boilers, which was 
the cause of the explosion. 

The Tri-Color burst her low pressure boiler while 
lying at the Wheeling wharf, and killed seven or eight 
persons. The Wyoming, Kanawa, Kate Fleming, Lu- 
cy Walker, Louisiana, and many other boats have 
burst their boilers, though we cannot say whether they 
were all lying to or not when the explosions took 
place, but we are inclined to think they were making 
ready to put out when the accidents happened. 

We will now make some remarks with regard to the 
collapsing of flues. We saw a steamer called the 
Chochuma that was said to have collasped her flues 
while under way just below the Falls of the Ohio, 
on her trip downward. We saw her in the river, and 
noticed the steam flying around her bow. At that 
time they were trying to get her to shore on the Indi- 



28 THE PRACTICAL ENGINEER. 

ana side. Although it may seem strange to some that 
a boat could burst her boiler or callapse her flues while 
underway, yet it does not seem in the least strange to 
us so long as the steam is kept back by checking it off 
in the throttle-valve, in order to keep up high steam 
in the boilers. If the engineer should happen to have 
his throttle-valve a little too close, so as to work off 
less steam than he makes, the boiler must blow off 
steam ; and if this should be the case, the engineer, 
not thinking the steam being throttled off so clcse to 
be the cause of its blowing off, they no doubt hang a 
wrench or two on the safety-valve lever, and in this 
way overload it and explode the boiler or collapse the 
flues while the boat is under way. 

We have frequently heard of explosions when there 
was plenty of water in the boilers, and the engines 
running at the same time. This may be easily ac- 
counted for in the manner we have referred to ; but 
we do not think this has ever happened on the river 
while working off steam on the engine with an open 
throttle-valve. We think it bad policy to throttle the 
steam off too closely ; it causes the engine to labor 
more, and of course the boat must run slower. 

A boat collapsed her flue as she was putting out 
from the Pittsburgh wharf. One of her engineers was 
instantly killed and the other died next day. We saw 
both of them. Several others were scalded. 



THE PRACTICAL ENGINEER. 29 

The steamer Fashion collapsed her flue while pass- 
ing through the lock. She had a doctor on board, and 
no doubt there was a sufficient quantity of water in 
the boilers when the explosion took place, but she had 
too much weight on the safety-valve. 

To this, we believe, may be attributed the explosions 
of all the boilers heretofore alluded to. Of all the 
flues that have collapsed on the steamers above refer- 
red to, not one of them, that we are aware of, had a 
doctor for supplying the boilers with water in case of 
an emergency. And all the boilers (we except the 
Louisiana — -never having seen her, we are not positive 
as to the length of her boilers — however, we are in- 
clined to think they were short,) were shorter than 
those used on large steamers of the present day. 

Now, when we compare the long boilers with the 
short ones, we find that there is not one fourth the dan- 
ger of them exploding; nor can as much steam be 
made, in proportion to the amount of iron used, with 
long as with the short boilers. 



3* 



30 THE PRACTICAL ENGINEER. 

COLLAPSING OF FLUES. 

[ See page 18. ] 

As a general thing, the flues are not made as strong 
as the boiler hull. The flues of large boilers, 40 and 
42 inches in diameter, should be 1-16 of an inch 
thicker than the boiler hull iron ; that is, all flues 14, 
16, and 17 inches in diameter, should be 5-16 inch 
thick, and for 18 inches and upwards in diameter, the 
thickness of the iron should be increased in proportion 
to the increased diameter of the flues. 

Another cause of collapsing of flues is, the water 
being suffered to get too low in the boilers, and the 
dry part of the flue being exposed to the fire becomes 
weakened and gives way under pressure of the steam. 
And still another cause is, the carrying of steam too 
high in the boilers. Flues should be made as round 
as possible, for if they have flat places in them they 
are much more liable to collapse. 

We have never heard of long boilers, say from 30 
to 40 feet, blowing up. But we do not wish it to be 
inferred from this that they cannot be blown up. Now, 
when a boat is detained, for the purpose of discharging 
or receiving passengers, although the furnace doors 
and flue caps are thrown open, the fire remaining in 
the furnace is quite sufficient to explode or collapse 
the flues of the short boilers ; yet the same fire under 



THE PRACTICAL ENGINEER. 31 

the long boilers would not, nor could not do any harm, 
and if let alone, would burn out. To explode them at 
all would require additional fuel. A double length 
boiler, 40 feet, as we have already shown, will not 
generate as much steam as two 20 feet boilers, and the 
amount of steam less will be just in proportion to the 
difference of heat in the first 20 feet of the boiler, 
where the fire lays, and the last 20 feet, where it is 
much fainter. The heat of the fire being much strong- 
er, in proportion to the amount of iron used, and the 
water being carried much lower than at present, was 
one of the great causes of explosions of former days. 



CYLDINDER BOILERS. 

Cylinder boilers, from 18 to 30 inches in diameter, 
have frequently been tried for propelling light steam- 
ers, ferry boats, tow boats, &c. Those who used them 
no doubt thought they would answer a good purpose, 
but a few trials soon proved the contrary. We recol- 
lect of two steamers, the Harlem and the Franklin, 
that used them for a short time. The Harlem had five 
of these small boilers, 18 inches in diameter, and the 
Franklin four, of the same diameter ; but after giving 
them a fair trial, they were taken out and replaced by 
doubled-flued boilers. 

There are many objections to these small cylinder 



82 THE PRACTICAL ENGINEER. 

boilers : they are too small to be properly cleaned out, 
and a great deal of the heat is lost in the chimney. 
The heat from the chimneys, in warm weather, is a 
great annoyance, and the boat at all times is liable to 
take fire from it. 

The small cylinder boilers at best, are but poorly 
calculated for generating steam, and as a general thing 
should not be used on steamboats. 



DISTANCE BETWEEN BOILERS. 

It has been the custom to set boilers but 2 inches 
apart between the boiler heads, leaving, where the 
iron was not more than J inch thick, but 1J inch be- 
tween the hulls of the boilers; but at present it is 
quite common to have them 6 and 8 inches apart. 
This gives more fire front under the boilers, allows the 
flame and heat of the fire to get between the boilers 
to better advantage, and makes steam much sooner 
than if they were closer together. For proof of this, 
examine two boilers that are close together and they 
will be found black and sooty ; then examine two that 
are from 6 to 8 inches apart, and they will be clean 
and white, like a well-heated oven, 



THE PRACTICAL ENGINEER. 33 

HOW TO SET BOILERS. 

In order to set boilers on a level when the boat is 
in trim, fore and aft, some persons measure from the 
kelson up, allowing for the thickness of the deck plank, 
and thus make the boilers level or parallel with the 
kelson, fore and aft. The most simple and correct 
way, however, after the boat is equally trimmed, is to 
place a little clay in each end of the boiler flues and 
then put some water into them. Should the boat be a 
little more draft, at the head or stern, of course a pro- 
portionate allowance should be made. 



WEIGHT OF STEAM TO BE CARRIED. 

The experience and practice of our engineers proves 
beyond the shadow of a doubt, that the steam used for 
propelling boats on the Western rivers is sometimes 
carried too high. Explosions of boilers and collapsing 
of flues are of frequent occurrence. These things need 
not be — should not be. And, therefore, we think it 
is the duty of the government to set limits and bounds 
to the actions of those who go beyond reason, and 
know not where to stop. Those who thus recklessly 
endanger the lives and property of their fellow beings, 
have yet to learn their duty. Government, we say, 
should interpose its authority by regulating the weight 



84 THE PRACTICAL ENGINEER. 

of steam to be carried. Humanity demands this, and 
points to thousands of widows and orphans, left desti- 
tute and unprotected through ignorance or negligence. 
Is man his brother's keeper ? Most assuredly, we an- 
swer ; and government should prove the careful keeper 
of its subjects by framing efficient laws to protect their 
lives and property. Proper officers ought to be ap- 
pointed, whose duty it should be to investigate all the 
circumstances connected with the explosions of boilers 
and collapsing of flues, and bring the offenders to pub- 
lic account. 

We have been agitating this subject for some years, 
remarking the danger of carrying steam too high, and 
are glad to learn the government has taken the mat- 
ter in hand. We understand that it is carried from 
150 to 175 and up to 200 lbs. per square inch. Ac- 
tions speak louder than words, and we want no apolo- 
gies in justification of the past, but should see to it 
for the future that steam is not carried too high. 

All boilers 36 inches in diameter, made of \ inch 
iron, and the boiler heads in the proportion, having 
the flues full \ inch thick, might be safe in carrying 
130 lbs. of steam to the square inch. Th pressure of 
steam should be reduced in proportion to the wear of 
the boilers. All boilers 38 and up to 40 and 42 inch. 
having flues and boiler heads proportioned as above, 
boiler hull \ inch thick, full flues 5-16 inch, and boiler 



Fa.&e.35. 




THE PRACTICAL ENGINEER. 35 

heads 38, 40 and 42 inches, | thick, would be safe in 
carrying 120 lbs. steam to the square inch ; 44 and 46 
inch boilers 110 lbs., and 48 inch boilers boilers 100 
lbs. to the square inch. The hull of the 48 inch boiler 
should be 5-16 of an inch thick, scant, the flue 5-16, 
very full, and the boiler head f inch thick and double 
braced. The man plate should have a heavy ring of 
broad flat iron riveted around it, for the purpose of 
making it stiff enough to stand screwing up. 



FIRE FRONTS AND BACK PLATES. 

Heretofore, plain fore-fronts were made without any 
lining whatever, and consequently often become so hot 
as to scorch the clothes of the firemen. The fronts 
on which the boilders stood would frequently bend and 
give way under the excessive heat, and had to be re- 
placed often the same as we have now to replace our 
grate-bars. 



FIRE-FRONTS LINED. 

Fire-fronts have been made to receive different 
kinds of linings. Cast-iron liners have been fre- 
quently made, but were found not to answer the pur- 
pose on account of having to be often replaced with 
new ones. At the present time it is common to line 



S6 THE PEACTICAL ENGINEER. 

fronts with fire-bricks, which is by far the best plan 
of any yet adopted. Sometimes the liners that are to 
receive the brick, are cast on the fire-fronts, and at 
other times cast separately, and bolted on to the fire- 
fronts with screw-bolts. The latter is the best plan. 
These fronts are quite cool and pleasant for the fire- 
men, and seldom need repairing. Another great im- 
provement in fire-fronts would be to let the grate-bar 
bearer, in front of the liner, extend five or six inches 
beyond the liners for receiving another course of brick, 
the narrow way, b (or lengthwise, if you please, nine 
inches,) the casting to be, say 4J inches in the clear. 
This would keep the furnace doors still more cool, and 
be easier on the edges of the liners. The fire in this 
place can do no injury to the fronts or liners for want 
of air. [See letter b in brick, draft A, a side view of 
a boiler, page 50.] 



BURNING OUT GRATE-BARS. 

In order to prevent the burning out of the grate- 
bars, it is necessary that the ash-pit should be kept 
well-cleaned out. Some ash-pits require cleaning out 
oftener than others — depending altogether upon the 
depth. Formerly ash-pits were made so shallow as to 
require almost constant cleaning, and still they were 
continually burning out the grate-bars. Now they are 



THE PRACTICAL ENGINEER. 37 

much deeper, but still they must be cleaned out occa- 
sionally, yet not half so often as the shallow ones of 
former days. 



BACK PLATES. 



Back plates should be firmly fastened to the boilers. 
They are sometimes laid on top of the brick wall and 
on the top of the flue, with nothing to hold them fast 
to the boiler when expanding or contracting, and the 
result is, that the draft is partially destroyed, the 
smoke and sometimes sparks escape, making it quite 
disagreeable. There is also much danger to be appre- 
hended of fire from the sparks. The best plan for 
fastening them securely to the boiler, is to cast lugs 
on the back plates, drill holes in the lugs and boiler 
heads and tap them, and then fasten the plate to the 
boiler head with set screws, cover the joint over with 
mortar, and the job will be complete. [See hack plate 
on draft C, page 50.] 



38 THE PRACTICAL ENGINEER* 



STEAM AND STAND PIPES. 



CAST-IRON STEAM PIPES, 

The pipes used on the first steamers were made of 
cast-iron altogether. The steam pipe, from the boiler 
to the cylinder, had a stuffing box and a slip joint 
allowing it to come and go as the spring of the boat 
might require. The supply pipes, from the force 
pump to the boiler, were also made of cast-iron. These 
were the kind of pipes used on the Western steamers 
about the year 1820. They answered very well for 
slow running boats, but as the speed of steamboats 
began to increase something of a more malleable nature 
was required,— something that would yield and accom- 
modate itself to the spring or settling of the boat, and 
not be liable to break or crack. But a few years 
elasped however before this deficiency was supplied, 
and the cast iron were superceded by the copper 
steam and supply pipes, which proved to be far 
superior, and are still in general use. 

But we wish to call your attention more especially 
to the cast-iron steam pipes, now gradually going out 
of use. Where they were strong they answered a very 



THE PRACTICAL ENGINEER. 39 

good purpose. Frequently, no doubt, steam and stand 
pipes have been broken by the boat being ladened out 
of trim, or by its settling. Steam pipes are less liable 
however to be broken by the settling of the boat than 
stand pipes. Steam pipes have frequently been broken 
by coming too suddenly in contact with the shore when 
landing, or striking a bank or bluff, seriously injuring 
those on board by being scalded with hot steam. Pilots 
cannot be too careful in landing a boat, and should 
approach the shore as steadily as possible. 

Wrought-iron steam and stand pipes ? we think, are 
still better, and will soon come into general use. They 
will come and go without danger of suddenly breaking. 
In this they are similar to the copper, but in other 
respects they are vastly superior to the cast iron pipes: 
they need no joints, being riveted close to the boiler. 

We would recommend to all those who wish to fit 
out good boats to have wrought iron stand and steam 
pipes, and copper or wrought iron steam and supply 
pipes, from boiler to cylinder ? and from force pump to 
boilers. 



40 THE PRACTICAL ENGINEER. 

CAST-IRON STANDS CONNECTED WITH 
COPPER PIPE. 

The plan of cast-iron stands with copper connecting 
pipes was in use at an early day in the history of 
steam. The boilers rested upon the stands which were 
connected, one with the other, by copper pipes, on 
each end of which were stuffing-boxes, so arranged 
as to allow them to come and go. This, while it 
answered the intended purpose, was attended with 
great labor and expense. 



WROUGHT-IRON STEAM PIPES. 

Wrought-iron steam pipes, placed upon the top of 
the boilers, are considered a great improvement, as 
there is no danger from breaking or cracking from the 
settling or springing of the boat. Another advantage 
is the steam drum, on top of the boilers, — which acts 
as a small reservoir, and is a preventive to the draw- 
ing of water. If any water at all, may be drawn by 
the steam in this drum, it has a chance to go back 
and return again to the boiler. It is not good policy 
to have too large a steam drum. We would say that 
there might be as much capacity in the steam drum as 
in the two cylinders. If it goes beyond this, the drum 
will act as an unnecessary condenser. It acts as a con- 



•THE PRACTICAL ENGINEER. 41 

denser at the best ; still, it may be a necessary evil to 
prevent the drawing of water and give dry steam to 
use in the cylinder. 

It is not essential that the drum be very large, so 
that the openings from the boiler to the steam drum 
are sufficiently large to prevent the water from rising 
with the steam, as it is taken from the boiler into the 
steam drum. 



WROUGHT-IRON SUPPLY-PIPES. 

Wrought-iron supply-pipes are now coming into 
general use, and we would say that they are superior 
to any heretofore in use. There is one thing, how- 
ever, which we wish to impress upon the minds of per- 
sons fitting out large steamers, (or even small ones with 
large boilers.) It is, (and they should see to it,) that 
the last sheet of iron in the bottom of the boiler, on 
which the stand-pipe is riveted, and upon which one 
end of the boiler rests, should be f inch in thickness. 
It will then take a more general bearing upon the body 
of the boiler, than the small stand-pipe with a narrow 
flange can do. This we consider essentially necessary 
to the making of a better and a stiffer job than can be 
done without it. It is the lack of this stiffness in the 
boilers, at this point, owing to the small bearing of the 

stand-pipes on J inch iron, which causes them to spring 
4* 



42 THE PRACTICAL ENGINEER. 

up and down like a basket, or as though they were 
resting on a spring-board. When they come into rough 
water, or the waves caused by the passage of another 
boat, the safety-valve will spring up and down, bound 
and rebound, and causes the blowing off more or less 
steam, in proportion to its height in the boiler. 

We would say to those who wish the boilers to stand 
on a good foundation, try the recommendation above 
noted ; you can lose nothing by it, but will be sure to 
gain what we have mentioned. The boiler will be 
stiffer and firmer than it was on the former plan. 



THE DIFFERENT PLACES FOR ATTACHING 
STEAM AND STAND-PIPES TO BOILERS. 

As a general thing, steam is taken from the boilers 
at the most convenient place, to the engine. For our 
part, we do not think it makes much difference from 
what point it is taken. If we had our choice, and it 
was convenient to do so, we would prefer supplying at 
the back end of the boilers always, both river and land 
engines, and take the steam from the middle of the 
boiler, or from the end over the fire. But on steam- 
ers, some take it from the back ring of the boiler, some 
from the second, some from the third, some from the 



THE PRACTICAL ENGINEER. 43 

fourth, and some from the middle, &c. But we do 
not think that it would make any material difference 
where it is taken from ; we would prefer, however, to 
take it a little distance from where the water comes 
into the boiler. 



STEAM TAKEN FROM END OF PIPE. 

This is known by experience, to all those who have 
taken steam from two, three, and from six boilers, &c, 
at the end of the steam pipe, that it always draws the 
water to the side of the boiler from whence the steam 
is taken. On the side from which the steam is taken, 
the water will be found above the upper guage cock, 
while in the far boiler it will be below the lower guage 
cock. The diagonal line drawn on the six boilers 
[draft C, page 50,] shows the position of the water in 
the boilers. By the exercise of a little judgment in 
this case, the water may be brought very nearly to a 
level in the boilers ; by opening the furnace doors 
beneath the boilers furthest off from where you take 
your steam, and firing up hard under the opposite ones . 
But to do this and keep up steam, would require more 
boilers than would be otherwise necessary. The steam 
should be taken from double steam pipes attached to 
the center of a single steam pipe, where there are three, 
four, five, six, or more boilers, as seen on draft, page 50. 



44 THE PRACTICAL EK6INEE ft. 

STEAM TAKEN FROM THE CENTER OF A 
STEAM-PIPE. 

The very best place to take steam from two boilers, 
is from the center of the steam connecting pipe. 



STEAM FROM CENTER AND DOUBLE PIPE. 

To prevent the drawing off water from boilers, while 
using steam, the double steam-pipe has been invented. 
It is used for three or more boilers. This is truly a 
great improvement, as will be seen by the accompany- 
ing drafts — page 50. 



STEAM TAKEN FROM STEAM-DRUM 

On two-boiler boats, many of which navigate our 
rivers, the steam is taken from each end of a steam- 
drum. This is the safer and more practical mode for 
boats of that class ; but it is said to be better that 
three and four boiler boats should have but one pipe 
from the center of the steam-drum, branching off to 
connect with the two engines. For four, five, six, or 
more boilers, there should be two steam-pipes, taken 
from the back of the steam-drum to each engine. 






THE PRACTICAL ENGINEER. 45 



BRASS STOP-COOKS. 



DANGER OF BRASS STOP-COCKS BETWEEN 
THE BOILER AND THE FORCE-PUMP. 

Brass keys in stop-cocks, require to be tightly 
screwed to prevent them from leaking, and when thus 
secured, they are likely to corrode, and require the 
nut to be slacked off below, or the key to be hammered 
back, before they can be turned ; and unless there be 
a good thread and nut on the bolt below, they are lia- 
ble to fly out in the act of turning them. Every engi- 
neer has witnessed this fact. To turn the cock after 
it has been slackened will demand some effort to tighten 
it again. A slight frost will so far destroy brass keys 
that they cannot be used until repaired. Thus it will 
be seen, they are more troublesome than profitable. 

The only way in which they can be used with safety 
for stop-cocks, between the boilers and the force-pumps, 
is to screws the keys in with a bridle and a set screw. 
For this purpose, the stop-valve is used in its place, in 
which it is superior. 



THE PRACTICAL ENGINEBE. 



FREEZING OF STOP-COCKS. 

This is one of the greatest objections to the use of 
the brass stop-cock about a steam engine. They are 
liable to bo continually out of order, especially when 
subject to frost. They are more a matter of expense 
than profit. 



BLOW-OFF STOP-COCKS ON BOILER STANDS. 

This was the mode of blowing off the water from 
steamboat boilers in their early history ; they are, 
however, liable to get out of order in the several ways 
already mentioned. Their place has been superceded 
by the use of the blow-off valve, which is superior to 
the old plan. 



VARIOUS MODES OF CASTING CYLINDERS. 

It was customary to cast two nossles on the one end 
of the cylinder in the early days of steamboating, and 
upon tais plan were the majority of our engines con- 
structed. Laterly nossles were cast upon each end of 
the cylinders, 






THE PRACTICAL ENGINEER. 47 



FOUR LUGS CAST UPON THE CYLINDER, 

In early years, cylinders were made much shorter 
than those now in use. Four lugs might well do for 
them, while they would not answer for the long cylin- 
ders now in use. Every old engine has had the trial 
of them, and find that the keys could not be kept tight 
on account of the continual expansion and contraction 
of the cylinder. If, when hot, it were closely keyed 
up, there would be danger of the lug breaking when 
the cylinder contracted by cooling. Who has not 
experienced this in practical engineering ? The only 
way in which four lugs can be made to operate cor- 
rectly, is to key fast one on either side, and leave the 
other without keys. This will do, but it leaves the 
expansion and contraction confined to one end of the 
cylinder. 



FOUR NOSSLES CAST ON THE CYLINDERS. 



It was, for a long time, considered an improvement 
to cast four nossles on the steam cylinder ; because it 
looked better and was more pleasing to the eye than 
the plan previously used. It made an artistic job, 



48 THE PRACTICAL ENGINEER. 

SIX LUGS CAST ON THE CYLINDER. 

The casting of six lugs on each cylinder, has obtained 
for many years, and has been found of great utility. 
The cylinder is keyed fast by the center lug, and 
screwed fast to the cylinder timbers by the four end 
lugs. This gives the cylinder a fair chance to come 
and go, from the center each way. 



SUB-CYLINDER, 



In the early history of constructing steam engines, 
there was much uncertainty connected with the casting 
of cylinders. For the purpose of avoiding risk and 
difficulty, there is no doubt the experiment of casting 
the sub-cylinder was adopted. The main cylinder was 
cast without any nossles, and but two on the sub-cylin- 
der, which is bolted to the main cylinder; and the 
other two nossles are cast on the cylinder-head. 

The first engine of this construction was placed upon 
the steamer Hercules, and was afterwards used on the 
steamer Sampson. It was the only one of the kind 
which came within our knowledge ; and facts compel 
us to say, it worked admirably. It was constructed 
at Pine Creek, (near Pittsburgh,) Allegheny County, 
by Mr. Bellknap. 



THE PRACTICAL ENGINEER. 49 



STROKE OF CYLINDER. 

In the early days of steam, we used much smaller 
cylinders with shorter stroke than we now do, and 
worked steam, nearly full stroke on the piston, f to J, 
&c. Our cylinders in use at the present day, are 
nearly twice as long and large as those formerly used, 
and the steam generated in the boilers raised to a 
much higher pressure to the square inch. They cut 
off more closely in the cylinder, — -sometimes J stroke, 
f, and f, &c, in order to make as much from the 
expansion of the steam as possible. 

The remarks in regard to the long and short boilers, 
may well be applied to the long and short stroke cyl- 
inders. When persons are about changing from one 
thing to another, and find the change for the better, 
they are apt to carry it to the contrary extreme, and 
over do their work in their search after expediency. 
The medium stroke, between the long and the short, 
as a general thing, is the safer, more econominal, more 
powerful, and of more utility for all practical purposes. 

We could add much to this, but defer it till a more 
fitting opportunity. 



50 THE PRACTICAL ENGINEER. 

BEARING, THICKNESS, AND WIDTH OF 
SLIDES. 

Slides should be so made as to have a large bearing 
on the part where the shoving-head jaws are to run, in 
order that they may bear up under the weight of heavy 
pitmans, shoving-head, piston rod, &c, otherwise the 
cylinder cannot long continue in line. Our slides for- 
merly had not more than one half the bearing they 
should have had, to stand the wear they were subject 
to, and which the necessities of the boat which they 
were propelling required. 

The slides should be much thicker than they are 
ordinarily made, so that both the bearing and the bal- 
ance of the slide, will not spring in screwing down. 
Slides are very often made too narrow, and by reason 
of this, they do not get a sufficient bearing upon tfie 
timber to keep them from rolling. There is another 
thing which should, as much as possible, be guarded 
against ; that is, the putting of "bolts in a straight line 
in the center of the slide, as may be seen in plate F. 
They should be placed out and in, as may be seen in 
draft, plate K. 

On the timbers H, may be observed another mode 
of putting on slides, which was in use in the early 
stages of steamboat navigation. See plate H. 



Psu$e VJ 



1 ^j£f 


=^=^|^yjj 


'^jj* 


i- — 






|| ft 


OF 


° 1 




Slides. 










3 


3 3 T ' 






I 


n 


1 ° *■ 


o 1 


Taie, 50. 


■^ 






9 H. 

Li 




D 



nCJ 




TdJc.50. 




THE PRACTICAL ENGINEER. 51 

LENGTH OF SLIDES. 

The length of the slides, for river engines, should 
always be from one to one and a half inches shorter 
than the stroke of the engine and the guage shoving- 
head, so that the jaws will work over the slide at each 
end in such a manner as to keep a lump from rising on 

the end of the slide, as would inevitably be the case 
were the slide longer than the stroke of the engine and 
shoving-head jaws. If the slides be longer than this, 
and the jaws screwed close to the slides, to keep them 
from back- lashing on the slides, which they are likely 
to do, in proportion to the amount of room or space 
left between the shoving-head jaws and the slides. If 
the jaws are as close to the slides as they should be, 
and the slides longer than we have mentioned, after 
having been worn for a season, they will have a raise 
on each end of the slides, just equal to that which has 
been worn down ; and as the pitman shortens by wear, 
it forces itself upon the thick part of the slide and may 
stress the thread of the bolt, thus causing the engine 
to labor as it revolves over the center, especially if it 
pinches tight on the slides. 

If backing be put in, to lengthen the pitman, it will 
work the same at the other end of the slide. This is 
the reason why we think it would be better to have 
the slides a little short ; thus you need have no charge 



52 THE PRACTICAL ENGINEER. 

on your mind for the safety and security of the engine. 
All intricacies about engines, beyond what is abso- 
lutely necessary, should be avoided. They not only 
tend to confuse and puzzle the engineer, but cause 
them unnecessary labor. The more simple the engine 
can be constructed — so that it has all necessary appli- 
ances, the better ; it will take less labor to manage it, 
and engineers are well aware that they have little time 
to lose while running the plainest and best engine. 



SHOVING-HEADS BORED OUT. 

Shoving-heads should always be bored out in a lathe. 
The center of the wrist on the shoving-head should be 
parallel with the center on the lathe, while the opposite 
end is being bored out. 

We could add much to this branch of the commen- 
tary ; but forbare, for want of room. 



BOLTS FOR SHOVING-HEAD JAWS. 

It is within my recollection of once having witnessed 
a steamer with four boilers. Were it necessary her 
name could be given. She had twenty-four inch cyl- 
inders, and from five to six foot stroke. We give it 



THE PRACTICAL ENGINEER. 53 

not as a certainty, but as recollection warrants. £he 
bad but one bolt in each of the shoving-head jaws, 
and we understood from the engineers that it answered 
the purpose for which it was intended. 

We do not approve of shoving-head jaws, large or 
small, with only one bolt. They are not safe, for this 
reason : there is nothing to prevent the bolt from work- 
ing out, if the nut happened to be a little slack. The 
bolt will instantly drop from its position, because there 
is nothing to hold it. In order to keep the nut from 
turning and working it should be a little tight — that 
is, the nut on the end of the bolt. The bolt will then 
drop out while the engine is working ; unless a jam nut 
be used. 

It is within the knowledge of many engineers, that 
this has happened, even with two bolts in the jaws. 
When this has happened, the nuts were made fast from 
turning, by a piece of wood being drove between the 
nuts ; the bolts will then sometimes, after all preca^ 
tions, turn, and find their way out. 

The object we have in view, in reference to two and 
three bolts, is, that the nuts upon the shoving-head 
jaws may be locked so that they cannot be turned ;. 
this may be done by driving a piece of wood betweea 
the nuts. If this should not answer, it is necessary that 
the bolts should be kept from turning, This may be 
done in two ways ;. one is by having square holes in ; 



5 



54 THE PRACTICAL ENGINEER. 

the lower jaws ; the other is, by making such large 
heads upon the bolts, as that they cannot pass one 
another. The latter is considered the easiest plan and 
will answer all useful purposes. In this way, and by 
these means, the nuts may be held fast to the bolts. 

The reason why two or three bolts should be preferred 
in a shoving-head jaw, is simply this : when they are 
secured, as above mentioned, they are safe in the 
hands of any person, whether he understands his busi- 
ness or not. It would also be safe in the hands either 
of a fireman or a boy, because the bolts are thus ren- 
dered stationary, until they are unlocked by drawing 
out the wood or iron which may have been put in 
between the nuts for the purpose of holding them fast. 
Now, by way of contrast, the author will give his 
views, while he feels the spirit and interest of the sub- 
ject strongly upon him. The subject now in review, 
may seem a small matter, but it is truly important. 
In the beginning of the lecture upon this branch, it 
will be remembered that strong objections were made 
against the use of but one bolt in the jaw of a large 
shoving-head, for the reason that it might possibly work 
out. It might do so, in case of friction produced 
by working dry slides, or from other causes, which 
nothing but experience and practice can avoid. 

It should be impressed upon the minds of all who 
read and understand what they read, that that which 



THE PRACTICAL ENGINEER. 55 

is perfectly safe within itself and completely under the 
control of one man, would be quite dangerous and 
unmanageable in the hands of another. Now, the 
author can, and there are many others within his 
acquaintance who can take the largest steamer that 
floats on the Ohio, and run her engine with safety 
with but one bolt in the shoving-head jaw, provided that 
bolt is as perfect as it ought to be when it comes from 
the hands of the machinist who forged it. The nuts 
should not be loose upon the bolts, but should on the 
contrary, be so tight as to turn easy with the short 
wrench, accompanied by the use of a second wrench 
to hold the head of the bolt below. They must be 
screwed hard and fast to. the papers between the shov- 
ing-head jaws, in order both for safety an:l us 3. If 
the slide be constructed on the long order, as hereto- 
fore described, as the pitman shortens it will crowd 
upon the thick part of the slide, and be very likely 
to strip the thread or break the bolt. Herein lies the 
difficulty with all but the most experienced engineers; 
for, if the nut be put on slack, or loosely, as it is in 
many other places, the engine will become unsafe and 
unmanageable. All having control of steam engines 
should be careful to understand this, as much harm 
might readily result from neglect, carelessness or inex- 
perience. Therefore, it is better that two bolts be 
used ; because, where the inexperienced may not be 



56 THE PRACTICAL ENGINEER. 

able to get along with one bolt, the scientific man 
might work his engine with a bolt even of smaller 
dimensions. The one would not know how to keep it 
in position. A jam nut might answer the purpose, but 
there are many who have not sufficient constructiveness 
to think of such an expedient. 

But, lest the length of the remarks upon this branch 
should weary the reader, it may be said in conclusion, 
that although some persons can work with but one bolt 
where others could not, on account of the superior skill 
and judgment which some possess in a greater degree 
than others, yet it would be the sounder policy, that 
all engines from the smallest to the largest, which have 
labor to perform, should be supplied with two bolts to 
the smaller and three to the larger, for the reason that 
if by chance or accident one bolt should break, the 
other one, or two as the case may be, will altogether 
likely hold out until it has been discovered wherein the 
weakness consists. 

It may well be considered a nice matter, where 
paper is used in a shoving-head, to so adjust it as that 
in every way it shall fit on the slides, both above and 
below, as well as upon the outer and inner edges of the 
slides. There is a great degree of skill required on 
the part of those wiio undertake this difficult job, to 
accomplish it as it should be done ; and when it is well 
done, it is, in many respects, far superior to any set 



THE PRACTICAL ENGINEER. 57 

screws which may be used for regulating the brass 
liners which are moveable on the jaws. 

There has been much said on this branch of the 
treatise, and much more might be said, but prudence 
requires that it should be cut short, as there are other 
branches that require attention. 



LENGTH OF PITMANS. 

It used to be a general rule to make pitmans three 
times the length of the stroke. Some have used them 
shorter than this, say about two and a half lengths of 
stroke ; but these are considered, however, exceptions 
to the rule. It has been customary for rolling-mills 
to construct their pitmans one foot longer than three 
lengths of the stroke. We do not vary but slightly 
from this rule at the present day, in the constructing 
of land engines. But for river engines, they should be 
about four times the length of the stroke as a general 
thing. There may, however, be exceptions, and more 
or less length used in order to accommodate the pecu- 
liarities of the engine for which they are intended to be 
used. There maybe forcible objections urged against 
the use of long pitmans. They not only are more 
liable to spring in their working than short ones, but 
add much to the weight which bears upon the top of 



58 THE PRACTICAL ENGINEER. 

the slides, and on the crank-rists to which they are 
connected. Thus it will readily be observed that the 
friction must be greatly increased. There is a medi- 
um between the long and short pitman which should 
always be observed by the builder. Extremes ought, 
in all cases, to be avoided. 



WOODEN PITMANS. 

The pitmans of our steamers are mostly, if not, in 
fact universally made of wood, (light pine wood,) and 
this had been found to answer the purpose admirably, 
when carefully watched and kept in perfect working 
order. Exceeding caution should be observed in the 
adjusting of the pitman straps, in order that the tim- 
bers be not cut too lean next the brass boxes ; because 
this would, w T hen screwed up, throw the jaws too wide 
apart at the point. 

On Eastern American rivers, as also on Ocean 
steamers, pitmans are all made of wrought-iron. A 
wooden one would be as great a novelty to them, as a 
wrought-iron one would be to those who navigate the 
Western waters. 



THE PRACTICAL ENGINEER. 59 

IRON PITMANS. 

Iron pitmans for the most part remain about the 
same as when first constructed ; but wooden ones 
require continual watching, and more or less screwing 
up, as the timber from which they are made, shrinks; 
and moreover, there is much danger from their liability 
to rot. The exposure to which they are subject, in all 
kinds of weather, is certain, sooner or later, materially 
to affect them. This fact requires vigilant watching 
on the part of those in charge of river engines. 



PLACING IN WRISTS, 

In order that wrists may be kept firmly in their 
place, it will not answer to give too large a draft, 
because the larger the draft, the more wedge-like it 
becomes ; hence the easier pulled out. It ought not 
to taper more than one fourth of an inch to six inches 
in length, and give three-eighth draft in the key-hole ; 
when drawn firmly up, split the key and all will be 
right. 



COLLAR- WRISTS AS FORMERLY USED. 

(See plate 4, A.) This was a bad way of putting 
in wrists, and the only object that could have induced 



60 THE PRACTICAL ENGINEER. 

its adoption must have been to save a little iron on the 
back of the collar, which costs more labor in its con- 
struction than the difference of iron would amount to. 
If this wrist should at any time be drawn up to tbe 
collar, and should happen to work loose, it could not 
be ascertained by reason of the collar, without especial 
attention. If it be found loose, the only remedy is to 
take it out and bush it. It would be found that the 
fault consisted in making the wrist too small to allow 
sufficient bearing to hold itself in form without chaw- 
ing and working loose. 



WRISTS, AS NOW USED. 

Either of the secured wrists wiJl answer the purpose. 
(See diagram H, No. 5,) the wrist B was brought into 
use long after the use of the wrist A, which has here- 
tofore been fully alluded to. It was of greater utility, 
and worked to to better advantage, because it had no 
collar to prevent its being drawn up if slack ; nor had 
it any obstruction to prevent its being bushed, if found 
necessary. 

It was found to be much more convenient, and far 
more practical, because it worked more easily. It had 
no collar to look after and fit in, or see to when it 
became loose ; nor had it any play from the motions of 



THE PRACTICAL ENGINEER. 61 

the engines. By use of a large wrist, there is greater 
strength and more bearing, which prevented hard 
keying and heavy pressure upon the wrist, when per- 
forming its labor, from bedding itself in the eye, as a 
small wrist will always do. 

C, is a wrist which is larger on the back end ; this 
was found necessary from the use of wrought-iron 
cranks, on account of boring out the holes, both of them 
true from one side, without changing the crank in the 
lathe ; whereas if it were changed, in order to bore out 
the other side, it would be almost impossible to get the 
two holes as true to each other as on the former plan. 
The outside collar is sometimes separate and screwed 
on with a set-screw. The only object of this would be 
to save iron ; it is bad policy, although it has in many 
instances been found to operate well. In many more, 
it might be found the cause of much trouble. The 
wrist should be in one piece, as may be seen in plate L 



WRISTS WITHOUT KEYS. 

This plan has been introduced lately upon the 
Western waters. It is the putting in of wrists, in the 
cranks of our steamboats, without keys. They are 
made with little or no draft, and are forced in by 



62 THE PRACTICAL ENGINEER. 

means of a screw, which being properly adjusted, the 
wrist is riveted in, or hammered a little around the 
outside edge of the wrist. This plan has been practi- 
cally tried, and many engines bear testimony that it 
has answered the purpose admirably ; but in all cases it 
would be much better that the wrists should be firmlv 
keyed in. 

If it becomes necessary that a wrist should be taken 
out, which has been forced in and burred, it would, 
beyond doubt, become necessary to take off the crank 
and carry it to a shop in order to have the burr cut off ? 
and it will require to be placed above a screw in order 
the more conveniently to take it out, 



THE PRACTICAL ENGINEER. 63 



PILLAR BLOCKS, 



BOTTOM BRASSES IN PILLAR BLOCKS. 

In the early history of our steamers, as a general 
thing they made no use of bottom brasses, but instead 
thereof used side brasses, considering this sufficient, 
inasmuch as the labor of the engine is principally fore 
and aft upon the side boxes. Notwithstanding this, 
there was still found to be considerable wear on the 
bottom blocks, owing to the weight of the main shaft 
and fly-wheel ; and owing to a little wear of the pillar- 
blocks (by lack of the brass) the whole block might 
be lost ; which otherwise, would last as long as the rim 
of a fly-wheel that would be as good when the boat 
is worn out as on the day when it was placed on 
board. 



64 THE PRACTICAL ENGINEER. 

KEYS IN SIDE BOXES. 

Side boxes are frequently keyed up to the journals 
by means of narrow keys through the caps, with four 
holes cast in the pillar-block, for the purpose as well 
of securing the keys as they are driven down, as that 
of keeping the side-boxes tight to the journals. Objec- 
tions to the use of these keys may be urged for many 
reasons ; they weaken the cap as well as the pillar- 
block ; they may slip back and leave the boxes loose ; 
and being thus exposed, at all times, to view, they may 
often be driven down where there is no occasion, and 
thereby heat the shaft, and produce unnecessary fric- 
tion. They are also liable to cut the shaft and boxes 
unnecessarily. 



BACKING IN SIDE-BOXES. 

This mode may be considered much better than any 
other plan now in use. When the boxes are once 
keyed up to the place, and the caps on, there is no 
danger of your backing coming out ; and at any time 
when side-boxes are becoming slack, the cap can be 
taken off, (which should be done immediately on dis- 
covery of looseness,) the slack may be taken up by 
putting in a thin piece of sheet-iron. 



THE PRACTICAL ENGINEER. 65 

BORING OUT PILLAR BLOCKS. 

To make anything like perfect pillar blocks, it is 
absolutely necessary that they should be bored out as 
smoothly and as true as a cylinder, and each pillar 
faced off on each side perfectly true in the lathe. 



LARGE COLLARS ON SHAFTS. 

Our large steamers should all have large collars on 
each side of the journals, varying from one to one and 
a half inches, as the collars on the shaft always bear 
hard on the pillar blocks when the boat is on a list. 
Thus it will be sufficiently plain that a false motion is 
continually on the increase ; this can be remedied by 
cutting the side-boxes in two pieces and driving a key 
between the brass and the collar on the pillar blocks. 



SMALL COLLARS ON SHAFTS. 

In the early years of steam boating there were 
four shafts, and they all had small collars. In a very 
short time during the running of the boat these collars 
would be found to have bedded themselves in the pil- 
lar-blocks on both sides ; and this, in addition to the 
6* 



66 THE PRACTICAL ENGINEER. 

back lash in the coupling blocks then in use, would 
make a tremendous noise as the boat would roll from 
one side to the other, while making short turns, which 
would be quite as unpleasant to a nervous or sensitive 
person, as the sound of trip-hammers. 



IPa.ge.67. 




THE PRACTICAL ENGINEER. 67 



CAMS 



SETTING THE FULL STROKE CAM. 

These cams are made in two pieces, pivoting up and 
down straight through the center ; thus when the 
engine is on the after dead center the cam stands 
straight up, and square up from the top of the pillar 
block, when the block stands level with the boat fore 
and aft, or in other words stands parallel with the 
shear plank. 

The pillar blocks now in use differ materially from 
those formerly used. They are not put down parallel 
with the shear plank, but are laid on an inclined plain 
in a line with the cylinder and the slides. This is 
owing to our cylinder timbers being quite differently 
made from those of former years. 

Our cylinder timbers now are skeleton timbers, and 
they run the whole length on an incline. Those in 
use many years ago, were filled up of different pieces 
of timbers, solid, while the cylinder timbers, generally 
in this case run on an incline up to the pillar block, 
and then this part of the timber was level or parallel 



68 THE PRACTICAL ENGINEER. 

with the shear plank, and the pillar block would be 
parallel with the same. In this case, as we have already 
described, the center of the cam would then stand 
plumb up, or square up from the face of the pillar 
block and the center passing through each half of the 
cam stands upright and parallel with one or both faces 
of the cam frame, ( as may be seen in the full stroke 
cam and plate, which has a cut off cam mostly 
within the same.) 

The sitting of the full stroke cams on our engines at 
the present day, where the cylinder timber is on the 
incline, and straight on the top the whole length of 
the timbers the center of the cam is still as above 
described, parallel with one or both faces of the cam 
Tame, and of course, the center of the cam is square 
up from the face of the pillar blocks, the same as the 
one first mentioned, where the pillar blocks were level 
or parallel with the shear plank. There is, however, 
this difference : on the plan which obtained in early 
years, the pillar blocks being parallel with the shear 
plank ; in this case, the faces of each cam would 
would also be plumb, or in other words, both faces of 
the cam frame and the center of the cam would be 
square up from the center of the pillar block ; but the 
faces of the latter, being on an equal inclination with 
that of the cylinder timbers, (as they are now used,) 
the center line through the exhaust cam hangs as much 



THE PRACTICAL ENGINEER. 69 

over the plumb as the face of the pillar block in the 
same length of cam is below the level. 

It should be remarked that neither the plumb nor 
the level is used on water crafts, but the author has 
made use of them, in this treatise, in order that he 
may be the more easily understood. If the top of the 
pillar block is level when the boat is in trim, the cen- 
ter of the cam would be found perfectly plumb. To 
repeat the substance of what has been already said in 
regard to the setting the exhaust or full stroke cams, 
when the engine is on the after dead center ; when the 
nose of the cam is up and the center line, through the 
middle of the cam is always found to be square up 
from the middle of the face of the pillar block, and of 
course the center line through the cam will be parallel 
from one or both faces of the cam frame ; and the 
easiest manner in which these cams can be set, is to 
make the center line through the cam frame parallel, 
or at equal distances from the face of the cam 
frame ; thus that frame will be equi-distant from the 
center of the main shaft. This rule will always be 
found right. It makes no difference if the pillar blocks 
are on a level with the shear planks, or on an incline. 
The principle remains one and the same, for horizon- 
tal or incline engines. 

After the full-stroke cam has been set, it is advisa- 
ble to make a mark both upon the cam and upon the 



70 THE PRACTICAL ENGINEER. 

cam flange, (opposite the first one,) upon the shaft ; so 
that if this cam should slip either way whilst in the 
act of setting the cut off cam, there will be nothing to 
do but bring mark to mark ; and when the cut off cam 
is properly adjusted it would be well to mark it also, 
so that in case it should at any time slip by reason of 
the bolts becoming slack, or from any other cause, it 
will be much more easily discovered and adjusted, by 
comparing the marks made on the cam with those 
made upon the cam flange, or upon the main shaft. 

It should be well noted that double arms upon the 
rock shaft which is worked with a full stroke cam for 
backing, and sometimes for going forward, should be 
taken to the boat by the proper persons, and placed 
upon the cross shaft, and then the cam-rod to ship on 
both the upper and lower pin. The arm and rock 
shaft should be marked with a center punch and the 
hole drilled ; this is the most correct plan of perform- 
ing this part of the work. These arms are sometimes 
put on and drilled before coming to the boat; others 
put them on as before stated. 

To those who put these arms on the rocks in the 
shop instead of placing them on in the boat, on both 
pins while the engine is on the dead center, it will be 
well to say that they will sometimes require a little 
raising or lowering of the bearer of the cam-rod above 
or below a straight line, as it may require to make the 



THE PRACTICAL ENGINEER. 71 

cam-rod ship on both pins in the arm. It is to avoid 
this and also to keep the cam-rod bearers in a straight 
line, that mention has been made of the propriety 
of not making this arm fast in the shop where the en- 
gine is constructed ; but rather having it taken to the 
boat and there set, so that the cam-rod will readily 
ship on both pins. After which the arm should be 
marked, taken to the shop and drilled and made fast. 
This may be considered the safest and best plan for 
executing this part of the work. 

No. 2 is a draft of an equalizing arm, the object of 
which is to cut cff the steam equally at both ends of 
the slides inasmuch as the common cam has failed to 
do this ; the latter cut off the steam at the lower cen- 
ter, passing out slower than it comes in at the upper 
center. The reason of this will be discovered by exam- 
ining the shoving-head, when its center is in the cen- 
ter of the slide. For instance, suppose the crank to 
be three feet from center to center, when the shoving- 
head is in the center of the slide coming over the dead 
center the wrist will be about six inches over the cen- 
ter of the shaft, with a plumb, while on the other cen- 
ter going out it will be found six inches behind the 
time. This is why the nose of one cam requires to be 
considerably wider than that of the other; the defi- 
ciency must be made up in this way. The cam is par- 
tially double and has an off-set in the cam frame so 



72 THE PRACTICAL ENGINEER. 

adjusted as to accommodate the difference of the points 
as the cam passes over, as may be seen in plate No. 2. 



SETTING THE CUT-OFF CAM. 

Where the engine is on the after dead center, the 
nose of the cam is uppermost ; let the cam then be 
turned until the consecutive circle comes hard up on 
the face of the cam frame and ready to move it the 
moment the wheel begins to move over the center, (the 
face of both the cam frames, full stroke and cut-off, 
will be equi-distant from the center of the main shaft.) 

It is well in this place to make especial note that 
upright or walking-beam engines, the noses of the 
cams stand in an entirely different position to the 
crank upon the main shaft, to what those used on hor- 
izontal engines do. 

The reason why the center line through the nose of 
the cut-off cam does not stand perpendicular with the 
nose of the full stroke cam, is because it is a cut-off 
cam, and narrower on the nose, and on this acccount 
the center line forms an accute angle, as may be seen 
described on draft, cam No. 4f and No. 5. 

The sharper the nose of the cam the greater the 
angle, and the wider the nose of the cut-off cam the 
less will be the angle. (See drafts of different cams.) 



Paje.'l2. 




]L l^elZrewof eqn.ialijzuig, earn, on s afrit a 



*1 



THE PRACTICAL ENGINEER. 73 

NAMES OF A VARIETY OF CAMS. 

The following are the names of the various cams 
used for the puppet valve engine : 

Full stroke, or D cam, cut-off cam, eccentric cam, 
equalizing cam, and expanding cam. 

To give some idea of the latter cam it would be well 
to remark that it was in use on board the large steamer 
called the William French. It was buit at Jefferson- 
ville, about the year 1820. This cam is of double 
thickness, and the object of expanding or widening out 
the nose, was to enable the engine to work off more 
steam than she otherwise could, while in the use of 
good wood or other fuel. When, as is sometimes the 
case, the wood was quite green and of inferior quality, 
and would in consdquence generate less steam, they 
would be compelled to draw the cam together at the 
nose. But the full particulars of this cam will not at 
present be given, it having been so long a time since 
it was observed in operation. It was made in four 
pieces, and when expanded from its ordinary shape, 
some parts of the working on the frame would only be 
the one half thickness of the cam. The two inside 
half thickness of the cam should remain stationary and 
close, while the two outside ones opened at the nose ; 
and just as far as the latter passed beyond the former^ 
7 



74 THE PRACTICAL EN GINEBK. 

just so much must be taken off the heel of each inside 
cam. This is very difficult to be understood from ver- 
bal or written description ; it must be seen to be pro- 
perly comprehended, either in practical operation or by 
model, and then dissecting and laying it down in its 
different parts; which cannot well be done in this 
treatise. 

This cam will be, no doubt, a novelty to most rea- 
ders, but it was only our purpose in this work to give 
it a passing allusion, to gratify curiosity and stimulate 
a desire for more knowledge on this complicated ma- 
chinery. It may lead to important truths in the use 
of steam never before known. 

This cam when contracted and brought to its nar- 
rowest working point at the nose, required the two 
heels of the inside cams to be cut off as much as the 
two points of the noses of the outside cam extended 
over the inner ones. Say, for the sake of argument, 
the whole cam was three inches in thickness ; then 
some parts of it, while working in the cam frame, 
would be three inches in thickness whilst other parts 
would be but 1J inches thick — one half the thickness 
of the cam when closed together. 

If there should be a call for another edition of this 
work, the author will so prepare himself as to give a 
satisfactory explanation of the expanding cam. 



Pa.&e7jfc., 




THE PRACTICAL ENGINEER. 75 

SLIDE-VALVE CAMS. 

The names of the various cams used on slide-valve 
engines are as follows : 

Full stroke cam, eccentric cam, cut-off cam, (four 
points with one lean, and one full side opposite cut-off 
cam with six points with one lean and one full side.) 



VARIOUS CAUSES OF ENGINES LABORING. 

One great cause of steam engines laboring, is that 
the boilers are suffered to remain too long in use with- 
out cleaning. This requires more labor on the part of 
the firemen to keep up steam while a less quantity is 
generated by the use of the same quantity of fuel. 
While in this condition the boilers are liable to bag 
down and burn. They should by all means be kept 
clean. 



CLEANING FURNACES. 

The neglect of cleaning furnaces often proves a 
great drawback in the generating of steam, which 
causes the engine, while running, to drag heavily and 
labor hard. If the ashes are crowded up close to the 



76 THE PRACTICAL ENGINEER. 

boilers it will be found that the fire surface is measur- 
ably destroyed, while at the same time the draft will be 
greatly obstructed and the fire prevented from burning 
freely. The effect is easily seen in the running of the 
engine To those who have charge of land engines, it 
would be well to remark that they should see that the 
flue leading to the stack of the chimney be kept per- 
fectly clean. In many instances these have been found 
nearly closed with ashes. They cannot be kept as 
they should be without great care and attention, and 
it is indispensably necessary in order that the engine 
may run freely. 



FALSE MOTION IN THE CAM FRAME. 

It is to often neglected to gather up the false mo- 
tion in the cam frame. This is a matter which requires 
especial care and attention, as very much depends on 
this motion being kept right. It would be equally as 
bad policy to take steam too soon as it would too late, 
and should you have J, f, or even a half an inch false 
motion (false motion means no motion to the cam frame, 
and of course none to the valve with the exception of 
that which is thrown by the cam over and above the 
unnecessary space that is between the cam and the 
cam frame.) If the cam should throw four inches 



THE PRACTICAL ENGINEER. 77 

and there should be one half inch false motion of the 
cam frame, it would amount to the one eighth of the 
whole motion, which would be a dead loss. 



FALSE MOTION IN THE CAM— PAWS AND 
JOINTS. 

It is a well known fact to all engineers who have 
paid any attention to the working of cam paws, that 
as a general thing there is a great deal of false motion 
suffered to accumulate by wear, before stopping to 
have it bushed and placed to rights. In addition to 
this there is more or less false motion tolerated in the 
joints. 

Suppose there should be one-fourth of an inch false 
motion in the cam-paw, and one-fourth of an inch in 
the balance of the strap-joints connected to the same, 
it would amount to one-half inch, which added to the 
other half inch makes a full inch, and would be equiv- 
alent to one-fourth of the whole throw of a four inch 
cam ; and thus one quarter of the whole power of the 
engine would become a nullity, — a dead loss. This 
may, therefore, readily be seen to be highly important 
and worthy of serious attention by all practical engi- 
neers. 

7* 



78 THE PRACTICAL ENGINEER. 



CAMS MAY SLIP. 

Cams do sometimes slip. There may be several 
reasons ; one is, too few bolts to hold it fast ; an- 
other is, that the bolts may not have been screwed up 
sufficiently tight to hold it firm ; another is, that the 
cam frame may have been screwed up too tight, which 
will in this case heat and cause the cam to slip ; 
mother reason is, that the slide valve may have be- 
come dry for the want of oil, and grate and quiver, 
thus causing it to drive heavily. 

Another reason may be assigned for slide-valves 
grating and quivering ; and that is, that the valve-seat 
and slide-valve may both be alike very soft ; and it is 
a well known fact that two bodies of alike temperature 
will not work well in contact with each other, because 
there is too much affinity between them, and by rub- 
bing them together they become electrified and pro- 
duce heavy friction. 

There should always be different metals used for the 
valve-seat; one should be harder than the other, in 
order to work well together. 



THE PRACTICAL ENGINEER. 79 



SLIDE-VALVE SEAT OUT OF ORDER. 

This is often another gand cause of engines laboring 
and dragging. It arises from the valve and the valve- 
seat being worn out of true, and letting the steam blow 
through the exhaust opening without entering into the 
cylinder at all. There are many reasons for them 
wearing out of their true position, which time pre- 
cludes particularly mentioning in this volume. They 
may merely be hinted at and leave the reader to study 
the particulars at their more convenient leisure. One 
reason is, that the valve-seat has not been properly 
laid out and proportioned to wear evenly. The bear- 
ings in the seat may be much greater in some cases 
than in others, and the use of muddy water, filled with 
sand (as in the Mississippi,) may be and is another 
reason. The metal itself may be uneven, or it may 
have hard spots or places in the valve or valve-seat. 

This is a portion of the work which requires great 
care on the part of the builder and the engineer. 



80 THE PRACTICAL ENGINEER. 

PUPPET BALANCE AND CUP VALVES 
MAY LEAK. 

There may be a great waste of steam by reason of 
the above, unless the valves are properly attended to 
and well kept in order. The object of the balance 
valve is to make less friction and cause the engine to be 
more easily managed by the engineer ; this to some 
extent has been done. The single valve and seats in 
the opinion of many experienced engineers, will hold 
more tightly than it is possible to make a double valve 
and seat hold, on account of its having bearings to bed 
themselves upon two different seats. Single valves 
and seats can be made tight, but double ones are hard 
to make tight. It is a matter of doubt among some of 
our engine builders, as also with many practical engi- 
neers, whether they can be made tight at all. Many 
things appear to be true to the naked eye, that would 
seem to be very much out of true if the magnifying 
glass were applied. 



CYLINDERS OUT OF LINE. 

It is a well ascertained fact that cylinders are often 
used too long without being kept properly in line, and 
thereby great violence has been done to the engine. 



THE PRACTICAL ENGINEER. 81 

To work it when it needs to be lined, would be forcing 
it to do what ought not to be done under such circum- 
stances. 



CYLINDER OUT OF TRUE. 

Cylinders are often out of true in several ways, and 
many have been used that never were in true. 
There are probably as many out of true from the lat- 
ter cause as from any other. 

If a cylinder is anything like as true as it ought to 
be, when first started, it will run first without any 
packing in the piston head at all, and be capable of 
doing a great deal of work at the same time. Many 
new engines have been started to running in this way, 
and both single and double engine cylinders will wear 
out of true in course of time by constant running ; that 
is, horrizontal, not upright cylinders. 

The reason for this, is on account of the heavy 
piston head and rod constantly running on the bottom 
of the cylinder ; it will in the course of time, especial- 
ly if the metal be very soft, become somewhat elyptic. 

It would probably make but little difference in the 
running of the engine if the cylinder should be J- of 
an inch, or even J of an inch larger one way than the 
other, but it would not work with the metallic packing so 



82 THE PRACTICAL ENGINEER. 

well until bedded to the cylinder, but with hemp pack- 
ing it would do very well, and but little difference 
would be observed, A true cylinder is, however, pref- 
erable. Upright cylinders wear more evenly than hor- 
izontal ones. 



CYLINDER PACKING. 

It is well known that it sometimes happens that the 
cylinder leaks. Cylinders have been run until they were 
completely run clown for the want of packing. It is 
within the experience of many, that it has been used 
in the cylinder till it has become completely rotton. 
The steam has been seen blowing out through the heater 
while seaching for the difficulty, first apparent from 
the laboring of the engine. 

Again, packing has been known to be cut out before 
it had been much used and when still good. This no 
doubt was partly caused by small holes in the cylin- 
ders, and it is sometimes caused by the stroke being too 
long for the cylinder, when the packing in the piston- 
head comes nearly up to each opening in the cylinder. 
In case the pitman shortens a little by the wear of the 
boxes, it would bring the packing into the opening of 
the cylinder, and this would be an additional cause for 
the cutting of the packing. 



THE PRACTICAL ENGINEER. 83 

PACKING SCREWED UP TIGHT. 

Very often the cause of labor in an engine, may be 
traced to the screwing up the packing too tight. It is 
not necessary that packing should be screwed up as 
tight as it can be ; it is sufficiently screwed up when 
it is steam tight and this may be easily ascertained by 
letting steam into the cylinder, and observe whether 
it blows through the piston head before the cylinder 
head is put on, and while screwing up the packing. 
To make the packing any tighter than this would be 
to create unnecessary friction and cause the engine to 
labor. 



CAPS SCREWED TIGHT ON THE JOURNALS. 

This is too often done, and its discovery is frequently 
not made until the shaft and pillar block begins to 
speak in language not to be misunderstood, and tells 
to all within reach, who have not lost the sense of sight 
and smelling, that something is out of order. The 
oder produced by the heating of the shaft and pillar 
blocks is very offensive, from the burning of the grease 
and oil. Smoke may also be seen to arise from the 
same cause. The discovery is frequently made in this 
way. At other times it may be discovered by the 
labor of the engine, before it has time to heat. 



84 THE PRACTICAL ENGINEER. 

The pitman-keys on the crank-wrists, as well as 
on other wrists are sometimes driven too hard. There 
should never be one stroke too much nor too little. 
But if error should arise in this, it would be safer to 
be rather too easy than too hard. The other extreme 
is unsafe and dangerous ; not knowing what the result 
may be. The author knows of a pillar-block which 
was broken by driving down the backing of the side- 
box when it was almost down. One blow too much, 
in such places, will sometimes cause great injury. 



CAM-ROD. 



The cam-rod may have been altered. This has been 
the case frequently. After the cam-rod, and all other 
matters are set right, and the engine set running, those 
in charge of it not content to let well enough alone, 
have undertaken to try their hand at alterations, and 
have made the cam-rod or rods sometimes too long or 
too short. 



STEAM THROTTLED OFF TOO CLOSELY. 

No doubt this has often been a serious draw-back to 
the engines both upon water and on land. It makes 
no difference how much nor how high the steam may 



THE PRACTICAL ENGINEER. 85 

be in the boilers, if it be held back or choked off by 
the throttle-valve ; the benefit received from it is only 
in proportion as it is used in the engine. There is 
little doubt that steamers may have been exploded from 
this cause, as well as flues collapsed. 

An instance of this kind has been stated in another 
part of this work, which the author witnessed, while 
standing on the Kentucky shore, as a steamer was 
passing over the falls of the Ohio. She collapsed in 
the middle of the river while on her way down. At 
the time when he first saw her, the steam was flying 
all over the bow of the boat, and they were then try- 
ing to get her to shore, on the Indiana side of the 
river. (See particulars on page 27.) 

It is not probable that a flue would collapse merely 
because the steam has been throttled off, unless there 
was considerable extra weight hung upon the safety- 
valve when the boat is under way, to keep the safety- 
valve from simmering, or blowing off steam. This, no 
doubt, may be the cause, although unknown to the 
engineer : he may have the steam throttled off a little 
too close, so that the engine works off a trifle less 
steam than the boilers make while under way ; the 
safety-valve will then, as it should, begin to blow off 
the extra charge of steam that is accumulating. The 
engineer, not being altogether conscious of the cause 

of blowing off steam at this time, inasmuch as the en~ 
8 



8b THE PRACTICAL ENGINEER. 

gine at different other times worked off more steam 
than they could raise in the boilers — thinking there is 
no danger — he may hang on wo or three extra 
wrenches upon the safety-valve line, and thus imposes 
more upon the boilers and the flues than they are able 
to bear, and the consequence is that the weakest places 
in them will always first give way. The weakest part 
should always be the safety-valve; then all will be 
safe. 



HORIZONTAL FORCE PUMPS. 

The principal of force pumps is the same, whether 
horizontal or upright. The valves and the chambers are 
identically one and the same thing. The only differ- 
ence being that one has a horizontal barrel for the 
plunger to work in, while the other works in an upright 
barrel. This may be assigned as the reason why one 
is called horizontal and the other upright. The main 
object to be attained in using the horizontal force 
pumps, is the saving of labor and material to the buil- 
der of engines. It often, however, increases the labor 
of the engineer to keep them in order. The horizon- 
tal pump dispenses with the use of the pump stands 
and caps; the pendulum and pendulum shaft, the 
connecting link between the shoving-head and the pen- 



THE PRACTICAL ENGINEER. 87 

dulum and the connecting rod from the arm to the 
plunger. This is no doubt the object of using them in 
general. In some places there may not be room 
for an upright force pump, in which case it becomes 
indispensably necessary to use the horizontal pump in 
its stead. The latter suit better for short stroke en- 
gines than they do for long ones, because they are 
easier kept in line. When the brass in the shoving- 
jaws wears and settles down, it throws the end of the 
plunger hard upon the barrel of the force pump, and 
the end of the plunger begins to leak badly, by reason 
of this uneven wear ; and the longer the plunger the 
worse it is in this respect. Three different times has 
the author known a horizontal plunger to be turned 
down on this account, when a larger one had after- 
wards to be put in its place because of its becoming 
too small. More engines than one have had their 
plunger worn flat upon the point on account of the 
shoving-head sinking down on the slides by wearing, 
It is worthy to remark in this place, that when these 
pumps are put in line their centers should not be par- 
allel at both ends with the centers of the cylinder ; 
the end of the pump barrel next to the loose head of 
the cylinder, when the line is run through it parallel 
with the center of the cylinder, the engineer should al- 
low all clearance of the barrel on top of the plunger, 
mich would be keeping this end a little higher than 



88 THE PEACTICAL ENGINEER. 

the center of the pump-barrel line ; then, when the 
jaws settle down on the slides by wearing, the end of 
the plunger will be found to run twice as long as it 
would otherwise do, before it rubs the top off the pump 
barrel, owing to the clearance all being on the top at 
the far end of the pump. 



UPRIGHT FORCE PUMP. 

Upright force pumps, in a general way, are easier 
to keep in order than horizontal ones are, and usually 
put up true from the first ; so that on a good founda- 
tion they will need more lining while the engine lasts, 
Not so with the horizontal, it is continually getting out 
of line. The pump itself is stationary, but it is the 
plunger to which we allude, owing to the shoving-head 
sinking on the slide. 



UPRIGHT FORCE PUMPS WITH BORED 
CHAMBERS. 

This pump was considerably used in the earlier years 
of steam. It is the same in principle with the upright 
pump last treated of, only differing in this, that instead 
of using a plunger, they use a piston-head packed with 
hemp ; and the two valves, one on each side of the 
pump barrel, are at the foot of the pump. 



THE PR ACTIO AL ENGINEER. 89 



RULES HOW TO FIND THE STROKE OF A 
PLUNGER BY FIGURES. 

To find the stroke of a plunger by figures, it is ne- 
cessary to multiply the stroke of the engine by the 
length of the pump-arm, and divide by the length of 
the pendulum from center to center, and the product 
will be the stroke of the plunger. 

Example. — You want to find the number of inches 

throw of a plunger. The engine is five feet stroke, the 

pendulum is 72 inches long, and the pump-arm is 16 

inches from center to center. What number of inches 

stroke will the plunger have ? 

60 inches stroke of engine. 
16 inches length of pump-arm. 

360 
60 

Pendulum 72 inches ) 960 ( 13J inches stroke of plunger. 
72 

240 
216 

24 

| 72 | 3 



90 THE PRACTICAL ENGINEER, 

COLD WATER PUMPS. 

There is an endless variety of ways for raising 
water, but there is no plan which can be invented to 
do it which will require less power than the weight of 
the water to be raised, adding the additional friction of 
the pump to that weight. 

For raising water there have been invented the 
screw, working in an outside barrel; a variety of pat- 
ents ; rotary pumps of various kinds ; Mixwell's pat- 
ent double chamber pump with an air vessel ; War- 
ner's patent forcing and suction pump, &c. Here it 
will not be out of place to mention the kind of pumps 
we generally use : 

The common well or lift pump, with two boxes, — 
the upper and the lower box. This pump can raise 
water from 26 to 28 feet high. (See draft of a pump 
marked L) 

It is said that the pressure of the atmostphere could 
sustain a perpendicular column of water from 32 to 34 
feet in height. 



FORCE PUMPS. 



The barrel of this pump is generally made of cast 
iron, bored out true, in which a piston head works, 



Pace. 90, 



e c c e iftri e C sum. 





cut ol Ca.m. 



THE PRACTICAL ENGINEER. 91 

with hemp packing, screwed up with a follower, by one 
nut that screws it down, being attached to the pump- 
rod. This pump has one valve on the inside of the 
pump chamber, which is the receiving and discharging 
valve, and sits on a cast-iron pipe on one side of the 
pump and is screwed together ; the valve chamber has 
another branch pipe upon it for the purpose of carry- 
ing off the water as it may be discharged from the 
pump. 

This pump works as well as any one can, when in 
working order ; but in case anything should be the 
matter with the valve on the inside, the engine would 
be required to stop for the purpose of taking out the 
plunger before access can be had to the valve, to ascer- 
tain what the matter is. (See the draft of pump 
marked H.) 



SUPERIOR FORCE PUMPS. 

The barrel of this pump is similar to the last one 
about which we have been speaking, but the valves are 
both on the outside of the chamber, just as they were 
on the cold water force pumps. The fact of the 
valves being thus placed on the outside is what gives 
it superiority over any other pump that can be used, 
because access to the valves can be had at any time 



92 THE PRACTICALEN&INEER. 

without stopping the engine, and you can get through 
your examination in less than one fourth the time it 
could be done on former pumps. (See pump on draft 
marked R.) 



A SUPERIOR FORCE PUMP WITH AN AIR 
VESSEL. 

This pump is the same in all respects as the above, 
only with the addition of an air vessel, which is of 
great benefit towards relieving the pump from surging, 
where the water has to be thrown to a considerable 
height above the drum, as it gives elasticity to the non- 
elastic fluid, thereby enabling the pump to work more 
easily and smoothly, while at the same time throw- 
ing a more regular and uniform stream of water. (See 
plate S.) 

Drafts and disquisitions of other pumps might be 
given, but let this suffice for the present. 



THE PRACTICAL ENGINEER. 93 



THE FORM OF AN ORDER FOR A STEAM 
ENGINE. 

Persons in ordering steam engines are not sufficient- 
ly definite to be understood in regard to particulars ; 
and in handing in their orders, to receive proposals for 
the building of the same, as a general thing, they are 
too vague. They are sometimes written in the follow- 
ing manner : 

" Sir — I wish to know your price for a 14 inch cyl- 
inder, 4 foot stroke, with two boilers, 36 inches in 
diameter, 28 feet long. Put up at M'Keesport. 

" Please let me know your lowest. Yours in haste, 

Jas. Lowrie." 

Now, persons answering this letter may each have 
his own way of building such machinery. One may 
make it as light as he can, while another may make it 
heavy. Much depends in this case upon the principle 
of the man who is employed to construct the engine, 
whether he will come up to the mark, or whether the 
sizes must be specified and their fulfilment exacted at 
the hands of the builder. 

Now, the above order should be written thus : 

" Sir — I wish to know your price, and terms of pay- 
ment, for an engine of the following description : 14 
inch cylinder, 4 foot stroke, side valve, good plain fin- 



94 THE PRACTICAL ENGINEEK, 

ish ; main shaft about 13 or 14 feet between the jour- 
nals ; journals to be 8 inches in diameter, with bottom 
brasses ; fly-wheel 16 feet in diameter, rim 5000 lbs ; 
with two cylinder boilers, 36 inches in diameter and 
28 feet long, made of J inch iron ; a governor and a 
cold water pump ; well not more than 10 feet deep ; 
we will want about 20 feet of well-pipe, 10 feet between 
cylinder timbers and boiler wall ; to be ready by the 
middle of June, 1853." 

ANSWER. 

Terms as follows : half cash on contract, and the 
balance in two equal payments of ninety days each, 
with interest from date. 



THE PRACTICAL ENGINEER. 95 



GENERAL REMARKS. 



Single Engines, Double Engines, and Stern-wheel 
Engines — The advantages and disadvantages of 
one compared with the other — Stating which we con- 
sider the best, talcing all things intoconsideration. 

Single Engines. — Our steam engines, when first 
introduced upon our Western rivers, we made use of 
but one cylinder, using two main shafts and two water- 
wheel shafts which were connected by couplings. 
They were used for about thirty years ; and with very 
few exceptions they answered the purpose very well 
as long as we had nothing better. 

But we will now state some of the difficulties we 
had to encounter in the use of these engines. The 
passage way upon the deck was obstructed very much 
by the line of shafts passing all the way across the 
boat ; and it was found more difficult to keep these 
shafts in line, one with another, than the shafts on 
our single engines are. The coupling blocks wearing 
loose and often backlashing and breaking the coupling 
of the shaft, and sometimes the coupling block. In 



96 THE PRACTICAL ENGINEER. 

addition to this there would be a considerable power 
lost in the backlash of the engine. Backlashing is 
always lost power ; it is first acting then reacting, 
bounding and rebounding. Another difficulty arose 
from the fly-wheel cutting through the deck of the 
boat ; and then again one wheel would have to be un- 
shipped and go ahead with the other, in order to turn 
the boat, which took more time and required more room 
than the double engine does. These single engines, in 
general, only required two engineers ; and boats of 
larger sizes required a carpenter to attend to the 
water wheels and see to such repairs as are required 
to the boat. The single engine would cost a little less 
than double ones, and cost a little less expense for 
engineers than the others require ; but the difference 
is but little after all, as but one first rate competent 
engineer is required to take charge of an engine, 
whether single or double, and the wages of assistant 
engineers less in proportion. 

Double Engines. — Our river engines are now most 
generally used double, either for two side wheels, or 
for the stern wheel ; working with two cylinders. 

We will now treat upon the side wheels, with two 
cylinders, each separate" and independent of the other. 

The advantage of having two wheels consists in this: 
you have the deck of the boat clear from the back of 
the boilers to the stern ; the boat can turn in much 



THE PRACTICAL ENGINEER. 



97 



less room and time by going ahead with one wheel and 
backing with the other at the same time. And another 
great advantage may be found in the fact, that should 
one engine give out while under way, you can get along 
with the other until you make into port. These are 
some of the advantages which result from the use of 
the double engine, and the only objections which we 
are aware of, that may be brought against them, is 
that they cost a little more to fit them out than the 
single engine, and they require a trifle more expense 
to furnish two assistant engineers ; but when the ad- 
vantages of the double engine are compared with those 
of the single, and the difference in the cost of running 
the single engine, with the difference in the ctst of 
running the double, we say the side wheel double en- 
gine will be found far superior in the long run to that 
of the single engine, when all things are considered. 

We would here remark, for the information of those 
who are not aware of the fact, (and it is fare to suppose 
that many are not,) that although the double side 
wheel engines came into general use only about the 
year 1840, yet, they are no new invention, for it was 
in use something like twenty-five years ago, or about 
the year 1827. 

The author saw one of these double engines when 

on board the George Washington, as she was lying up 

at Shippingport, below Louisville. She had a double 
8 



JTO THE PRACTICAL ENGINEER. 

engine, with six boilers and three decks. Mention is 
made of this merely to show that here was an isolated 
case of the very same thing we are now using, and 
that it was in use about 27 years ago, and some 17 
years before they were introduced into common use 
upon our rivers. 

Stern Wheel Engines have their advantages as 
well as their disadvantages. The wheel being in the 
stern, they can get along in a narrower channel than 
our side wheel boats can do. They are also said to 
run better in strong water. Two engineers are suffi- 
cient to run one of these boats ; in case of any back- 
ing or going ahead, in the absence of one of the en- 
gineers, a fireman can ship or unship the cam rods of 
one of the engines, by direction of the engineer in 
charge of the other engine at the time. Now, it is 
stated by Haswell, in speaking of animals, that two 
men working at windlass at right angles to each other 
can raise 70 lbs more easily than one man can raise 
80. According to this calculation, two men working 
in this way could do one-sixth more work than they 
could if they were separate. Well, if the two cylin- 
ders working at right angles, gain power in the same 
ratio, (which it is reasonable to suppose they do,) here 
is a gain of one-sixth more power than those engines 
would have if used separate for the drawing of side 
wheels. Another advantage the stern wheel boat 



THE PRACTICAL ENGINEER. 99 

possesses, is that they can run during times of ice and 
drift when other boats can not, on account of their 
water-wheels being exposed to the floating rubbish, 
drift, &c. 

The first stern wheel steamer that was ever built is 
said to have been fitted out in Pittsburgh. She was 
constructed by Mr. Blanchard, to run up the Alleghe- 
ny. She was called the Allegheny and was built 
about the year 1830. We are not exactly positive of 
dates, not having been fully posted up in this matter. 
In the next, we will enquire more minutely into par- 
ticulars, and if possible give our readers the precise 
date. 

It will now be proper to point out some of the dis- 
advantages of the stern wheel boat, with our own 
thoughts thereon, and then leave you to draw your 
own conclusion. 

The engines being on the stern of the boat and the 
water wheel behind the stern, throws so great a weight 
upon that part of the boat, as to be liable to break it 
down, if not very stiff; and to bring the weight of the 
cylinders as far into the boat as possible, from the 
stern, some times very long pitmans are used. We 
object to over long pitmans being used. (For parti- 
culars see Pitmans, on page 57.) Another objection 
to the stern wheel is that it hides the view from the 
stern of the boat, which might otherwise be had while 



100 THE PEACTICAL ENGINEER. 

running. The boilers being placed in the bow and the 
engines in the stern, is well calculated to break a boat 
down at each end, while it raises her up in the middle, 
unless well braced and stiffened with timbers and bolts. 
Another objection is the great length of the steam and 
supply pipe which is required; the steam must neces- 
sarily condense considerably in travelling from the 
boiler to the cylinders, and thus the engines will be 
likely to work off a good deal of water in this way. 
(It is well here to remark that we are fully in the be- 
lief that the greater part of the water made from con- 
densed steam in the steam pipe might be forced to re- 
turn to the boilers, by placing the end of the steam 
pipe next the boilers a foot lower than that which en- 
ters the cylinders the water would run back to the 
boilers, and we do not think the draft of steam would 
fetch the water out ; it would settle to the bottom of 
the steampipe, and then run back to the boilers.) The 
water in the supply pipe also cools considerably in the 
long supply pipe, (which might be called a cooler,) 
whilst traveling from the cylinder to the boilers. 

The stern wheel boats require a great deal more 
room to turn round in, than either of the two above 
mentioned boats. This is owing to her motion being 
entirely straight ahead or straight backwards. 

But, notwithstanding all the disadvantages here 
mentioned against the stern wheel boat, she neverthe- 



THE PRACTICAL ENGINEER. 101 

less lias advantages more favorable than any other 
boat has. It can run in a narrower channel than any 
other boat can. It is not so likely to injure its wheels 
in putting out from shore ; it can run safer and better 
during floating ice or drift, and is said to run better 
in strong water than other boats can on account of 
stern wheels working more in an eddy. 

We have thus undertaken to point out the advan- 
tages and disadvantages of the different engines, leav- 
ing each to draw his own conclusion, after having read 
and heard ours, for we believe the perusal of this 
work may be the means of giving the reader new light 
on this subject, and of causing in him such thought 
and reflection as may be parent to some new ideas on 
this important branch of science. 

Double Engine Boats Superior.— We have al- 
ready given the reader to understand, that the double 
engine boats are far superior to the single engine boats 
built in early years ; and we will now state, in conclu^ 
sion, that side wheel boats with double engines make 
a much more beautiful appearance, when running than 
the stern wheel boats do ; this is owing to their supe- 
rior finish around the water wheel clear down to the 
guards of the boat. A stern wheel boat does not look 
so well on account of their water wheels being naked 
and exposed; and they are always rough and black, 

which does not contrast well with the finished painting. 
9* 



102 THE PRACTICAL ENGINEER. 

We would say to those who wish to build a neat 
boat, one that would attract the eye for its beauty, 
build a side wheel boat with an engine for each water 
wheel : but if you are not particular as to looks, and 
wish to have a small boat to run on small streams then 
build a stern wheel boat. 

Counter Balance. — The use of a counter balance 
is to put a weight on one side, to balance the weight 
that may be on the opposite side. Some of our ear- 
liest engines on the river, were put down on a level, or 
parallel with the deck of the boat ; in which case they 
require a counter balance equal to the weight of the 
crank, from the center of the shaft out, including the 
wrist and the half weight of the pitman ; nothing more 
than this was wanting. This counter balance was re- 
gulated by the fly wheel rim, being light on the crank 
side and heavy on the opposite side from the crank, 
just in proportion as the weight of the crank wrist, 
and half weight of the pitman required. But our wa- 
ter wheels are now made about one half larger in dia- 
meter than those of early years, which brings the 
shaft several feet higher up from the deck than they 
formerly were, and the cylinder is still kept down to 
the deck, as usual. This throws the cylinders quite 
on an incline, and they require more counter balance 
on this account, in proportion as the increase in the 
degrees of the height of the shaft. It is necessary, 



THE PEACTICAL ENGINEER. 103 

then, to get the number of degrees of incline ; then 
the weight of the piston head, rod, and shoving head, 
as also the other half of the pitman ; then in propor- 
tion as they rise on the incline with this weight, then 
will be required a similiar weight on the opposite side 
of the crank or wheel, in order to equalize the motion. 
Without this counterbalance, in coming up the inclined 
plain, the engine would scarcely be able to come over 
the center, and in coming over, it would pass down in 
such haste, that there would be danger of its driving 
all before it. Hence arises the necessity of a counter 
balance. 

Various ways op using the Counter-Balance. 
— Sometimes the opposite side of the crank was made 
heavy ; another plan was adopted of using a circular 
segment of cast iron, bolted on to the side of three or 
four of the water wheel-arms ; and another mode yet 
superior to this, was the casting of one or two flat 
pieces of cast iron, nearly the length of the buckets 
on the water wheel, 1J or 2 inches thick, 6 or 8 inches 
wide, (more or less than this, as occasion required) for 
a counter balance to the opposite weights. This plan 
was better than the segment on the side of the arms ; 
but all these are now dispensed with and three heavy 
buckets of double thickness, used in their stead. 



104 THE PRACTICAL ENGINEER. 

DEFECT IN FORCE PUMPS MADE IN EARLY 
YEARS. 

Very many of the valve-seat chambers in force 
pumps, used in the early days of steam, were made 
entirely too shallow. We have seen the top of the 
valve-seats, in force pumps, and check valve chambers 
about level with the opening in the bottom of the pipe 
leading from the valve chamber to the force pump, on 
the one side of it and on the other side of the pump, 
from the valve chamber to the discharge pipe, to which 
the pipe is attached that feeds the boilers with water. 
In some instances the tops of the valve seats were 
higher than this; in which case the valve stood the 
thickness of itself above the top of the valve seat? 
(with the exception of the level.) It is no wonder that 
force pumps, thus constructed, could not be depended 
upon at all times, to throw a regular supply of water 
into the boilers. 

In the first place, the valve when bedded in its seat, 
stands above the opening in the pipe ; and when raised 
by the plunger, for the purpose of letting the water 
pass through into the boilers, the valve being above 
the opening, it is thrown over on its side by the pres- 
sure back from the boilers, and sometimes remains in 
this position without falling ; and of course, while in 
this situation, it will throw no water. By frequent 



THE PRACTICAL ENGINEER. 105 

tapping with a hammer, the valve may be caused to 
fall into its seat ; it may then work a while ; but, after 
a short time, when the steam becomes a little higher, 
the pressure on the side of the valve will be greater, 
and the friction so strong that the valve cannot fall, 
when of course, the pump cannot work. 

We believe this to be the reason why many force- 
pumps refuse to do their part : it is because they were 
not properly designed by their constructors. We have 
seen and heard of engineers frequently throwing cold 
water on their force-pumps when their engines were 
running in order to start them to work when they had 
quit throwing; and they would beat the cap of the 
force-pump very frequently with a hammer, for the 
same purpose. Now, we ask what sense there would 
be in beating upon the cap of a force-pump, with a 
hammer, if it were not to bed the valve in its seat, 
which they must suppose to be up ? If it be up, let 
them ask themselves the cause, and they will find it 
to be just exactly as we have described it above ; viz : 
that the valve chambers were made too shallow to 
allow the valve seat to sink a proper depth below the 
opening of the pipe in the valve chamber. 

We do not believe the cause to be what many en- 
gineers have stated; "that the water was too hot, 
and that the force-pump was working steam," &c; but 
one thing is certain, the pumps frequently refused to 



106 THE PRACTICAL ENGINEER. 

work, and of course, some of our engineers would of- 
ten be put to their wits end to find out what was the 
matter. If a bystander were to ask them the trouble 
they would feel very strangely if they could not ans- 
wer him. And they (no doubt not knowing the real 
cause) would think it was occasioned by the water in 
the force-pumps being too hot when received from the 
heater ; but the true reason of the pump becoming 
overly hot, was owing to the valve being up on the 
discharge side of the force-pump next to the boilers. 
Suppose there was but a little leak on the opposite 
valve, between the valve and the seat, or between the 
valve seat and the valve chamber, owing to the lead 
having partially oxidised or wasted away. In this 
case the hot water would come back from the boiler 
through the pump into the heater ; this would make 
the pump as hot as steam could make it. 

We have laid down a draft of force pumps with 
shallow valve chambers, showing how the action of the 
water operates on the valve, by pressing it over to the 
one side, as may be seen in the valve B, in the draft 
of the force pump marked A. 

But perhaps some may suggest the idea of putting 
a bridle on top of the valve-stem, in order to keep it 
in its place, and from tipping over on one side. They 
can see the top bridle D in the force pump marked C ; 
but this bridle will not answer the purpose. The re- 



Ta<$< 




Pa^e.101. 




THE PRACTICAL ENGINEER. 10T 

active pressure being on one side of the valve, the 
friction becomes so great as to prevent the valve from 
falling. Engines running very slow might give the 
yalve time to settle and fall, while others would not, 
on account of the increased speed of their engine. 
There should be no friction of any kind whatever, to 
retard these valves from falling in the bridles or 
guards. Valve stems should fit easy. 



THE TRUE PRINCIPLE TO MAKE A COM- 
PLETE FORCE PUMP. 

We have laid down another draft of a force pump 
with a valve seat and chambers, as they should be 
made. The valve chambers should be deep enough to 
allow of a good depth of valve seat and a thick valve. 
The top of the valve, when up at a full opening, should 
never be allowed to come above the bottom of the open 
ing in the pipe, but should always be a little lower in 
the top of the valve than the opening in the pipe, say 
from J inch to an inch lower, according to the differ 
ence in the sizes of pumps. The reaction of water 
back from the boilers upon valves thus below the open- 
ings, will assist them to fall or close ; as the reaction 
or pressure of the water from the boiler comes more 
directly on the top of the valve, and hastens its fall. 



108 THE PRACTICAL ENGINEER. 

The valve F, in the pump E, is a model of a perfect 
pump. The top of the valve is below the opening in 
the pipe G, whilst the valve itself is up at a full open- 
ing. In this case, the reaction of water from the boiler 
passes over on the top of the valve (instead of striking 
on the side of the valve, as may be seen in the valve 
£ in the force pump A) and helps it to fall into its bed 
in the valve seat. 

HOW HIGH A VALVE SHOULD RISE TO MAKE THE OPEN- 
ING AROUND THE CIRCUMFERENCE EQUAL TO THE OPEN- 
ING IN THE DIAMETER OF THE VALVE. — This rule is 

very simple, and also very important that engineers 
should know it. It is equally useful to the builder of 
engines, to know how high his puppet valves should 
rise to give the same number of inches around the cir- 
cumference of the valve seat itself. It is useful also to 
know how high the force pump, check valves, &c. , 
should rise in order to give as much opening in the 
valve seat. The rule is this : 

The valve should rise one-fourth the diameter of 
opening in valve seat, measuring it at the smallest 
place, just at the bottom of the bevel. 

Example. — How high should a three inch valve 
rise, to give as much opening in the circumference as 
there is in the diameter : 

Divide by 4) | inches (0, J inches rise. 



Pa.gelOa 




THE PRACTICAL ENGINEER. 109 

And for a for a 4 inch valve — 

Divide by 4 ) 4 ( 1 inch raise. 
4 

T 
Table of inches of valves to give the same opening 
in the circumferences that there is in the diameter of 
the valve : 

Diameter of valves. Inches raise. 

Divide b y 4 ) 3 ........... .f inch. 

3|. ............ 13-16 inch. 



a a 



" " 3i | i n0 h. 

" " H 15-16 inch. 

" " 4 li„eh. 

" " 4i 11-16 inch. 

" " H Hinch. 

" " 4f..... ...... .18-16 inch. 

it (i 



u a 



5 ......... — 1J inch. 

5}............ If inch. 

" " 6 .. ....l*inch. 

it u 



« a 



•2 

6J............1| inch. 

7 . . — .... — If inch. 

8 ......... ...2 inch. 



10 



110 THE PRACTICAL ENGINEER. 

HOW TO CUT THE LEATHER FOR A 
PUMP BOX. 

To cut a leather out to fit a pump box, it must be 
cut circular ; and in order to get the small diameter, 
it is necessary to continue the. flare of the pump box 
until it meets in the center, and this will give the dis- 
tance for the inside circle ; and the outside circle will 
then be as much larger as it is intended the depth of 
the leather of the pump box should be. A box and 
leather may be seen laid down in draft ; A is the shape 
of the leather ; B is the pump box, and C is the cen- 
ter. It is upon this principle that strips for laying 
out boiler iron are made, owing to rings being smaller 
at one end than they are at the other. The difference 
of the diameter of boiler rings at each end, are equal 
to the difference of the boiler iron ; and the strips for 
laying out the boilers must be made accordingly. 



BEST KIND OF VALVE SEATS FOR FORCE 
PUMPS. 
The best kind of valve seats that can be used for 
force pumps, check valves &c. , are made of brass. 
Brass valve seats stand the water better than any 
thing else that has been tried ; iron seats soon rust out, 
and wear away much faster than brass. 



Pa^eJIO. 



xnrpi 



■yvebi C61R.J 



ytfgX er Fmip with an a re ve s s el 




SlLOwiryp kow to exit tlte 
1 e itkefl? of JL^iiDmR ox 

h, ft 



iPa^l 



Ft 



Bbr 



Fid 



/ 



^lve secct 



THE PRACTICAL ENGINEER. Ill 

We have seen another species of valve seats used as 
a substitute for brass ; it was made of cast iron, and 
in the inside of this valve seat there was a recess turned 
out, about f of an inch square, to receive a brass ring 
which was neatly turned to fit in this recess, which 
recess in the casting was a little larger at the bottom 
than at the top, so as to rivte the ring in so tight as to 
prevent it from coming out, as may be seen in the 
draft of the valve seat A, the brass ring B, after It 
was riveted tight into the valve, with a round faced 
chisel and hammer, it was then put into the lathe and 
turned off. "We have tried this plan and find it does 
not answer a good purpose on account of the brass 
ring becoming loose in the valve seat after using it a 
short time. We would therefore recommend brass 
valves and seats as being the very best that can be 
made use of for force pumps, check valves &c. 



BEST KIND OF MATERIAL FOR MAKING 
JOINTS GROUND VALVE SEATS. 

Brass valve seats have generally been put into the 
chambers of the force pump, and run in with lead ; 
but in course of time the lead oxidises and wastes away 
leaving the valve seat quite loose in the chamber, per- 
mitting the water to leak back through the joints. 



ui 



THE PRACTICAL ENGINEER. 



They are frequently corked tight with an iron kept 
for that purpose, and very often they are taken out 
and run in again anew ; but lead is continually giv- 
ing out, It does not stand in steam or hot water as 
well as it does in cold. 

Others put these valve seats in with tin ; this is much 
better then lead. Tin shrinks a little after it has been 
run in about the valve seat and requires to be made 
tight with a corking iron before using it. 

Others again have wondered whether cements would 
hold around brass valve seats. We have tried cements 
around brass valve seats For the purpose of testing it, 
&nd witnessing how it would answer, in asmucb as the 
lead was exceedingly troublesome. We have found 
the cement answers the purpose admirably ; it will 
stand firm from year to year, as tight as a bottle. 

Some bore out their valve chambers and turn their 
valve seats, so as- to make a tight fit, and then put a 
little red led around the valve seat and force it into its 
place, and it remains tight and permant also. It would 
require some little work to get these valve seats out* 
when put in this way. It is true, they seldom want 
taking out when properly put in, but it sometimes so 
happens that it becomes necessary to take them out 
for repairing. y 

(N. B. — It is worthy of especial note that these 
pumps which have very small valve seats, will wear 



THE PRACTICAL ENGINEER. 113 

out of order much faster than those that have larger 
seats and openings : and of course, would be required 
to be repaired much oftener.) 

We believe, upon the whole, that the cement is the 
very best material, and the very best mode for putting 
in force pumps and check valve seats into the cham- 
bers. There is no mistake about their holding tight.. 
Have a good, deep valve seat, and from J- to J of an 
inch all around for driving in the cement. Do nor 
have your cement space too large ; f of an inch would 
be too large if you can have less ; but if you cannot 
do better, perhaps even this will hold if your valve 
seat is deep. 

A great many valve seats are made entirely too 
shallow. A valve seat with a two inch opening should 
not be less than one and a half inches deep, A seat 
for a three inch valve, 2J inches deep ; and a 4 inch 
valve 2f or 3 inches deep. 



DIFFERENT CAUSES FOR STEAM BOATS 
TAKING FIRE. 

We were once present when they were getting up 
steam upon a new boat, for the purpose of running the 
engine when we discovered smoke arising from the ash- 
pan beneath the boilers. Alarm was given and it was 
10* 



114 THE PRACTICAL ENGINEER. 

immediately extinguished by throwing water under the 
pan as soon as it made its appearance. No doubt this 
was owing to carelessness on the part of the engineer, 
in not having water thrown into it, to keep it cool 
while raising steam, and while waiting for the engine 
to be put in motion to feed the pan with water. 

There would be less danger from fire, in case of 
carelessness in this way, if these ash pans were paved 
in with brick ; still, if well watered at all times, there 
would be no danger even without brick. Boats may 
have been burnt in this way ; and this may be consid- 
ered as one of the ways in which they may take fire 
through neglect. 

Another cause of steamboats taken fire. Not being 
able to particularize, we will merely say, that some 
sixteen or seventeen years ago, the Ben Sherod, an 
eight boiler steamer, one among the largest class of 
boats built in her day, caught fire in the night, on her 
way up the river from New Orleans, we think. It was 
reported at that time, that she was running a race with 
another boat when the fire broke out ; and the rumor 
was that they had been firing the boilers until they 
were red hot. This, of course, is not to be believed at 
all, for steam boilers cannot be made red hot wherever 
there is water in contact with the iron. But we will 
simply suggest several different ways in which steam- 



THE PRACTICAL ENGINEER. 115 

ers might take fire, and then point out the manner in 
which it is most likely for the Ben Sherod to have 
caught fire. 

In early days wood was universally used for fuel 
on our rivers, to raise steam ; and to a considerable 
extent it is Still used upon the trade below the falls of 
the Ohio. It was common and indispensably necessa- 
ry to have a rack or skeleton frame on each side of the 
fire bed, on the outside of the boilers, some ten or 
twelve inches off from the fire bed. This rack was neces- 
sary for several reasons : had the wood been piled up 
close to the fire bed, it might take fire, and if any of 
the brick wall on the inside would fall down, as they 
frequently do, the wood thus piled up would be sure to 
take fire. Now, the object of this rack was to keep 
the wood off from the fire bed, as well as to prevent 
the brick from being knocked down inside the fire bed, 
while carrying it aboard and piling it up. This work 
was usually performed by deck hands and deck pas- 
sengers, and of course they threw it down roughly ; 
often it would be sport to them to cause mischief. 

(ST. B. — To steamboat captains we would suggest 
that the wood should be carried in by the deck passen- 
gers, while it should be the duty of the deck hands 
belonging to the boat, to pile it up, for this being an 
every day business with them, they would fully under- 
stand the manner in which it should be done. On the 



116 THE PRACTICAL ENGINEER. 

ether hand, passengers are changing almost every day 
and if allowed to do this part of the work, (to pile wood 
on the boat,) they no doubt might occasionally throw 
sticks carelessly between the boards of the rack and 
strike the fire bed, and knock down the brick work 
within it. In this way fire might be communicated to 
the wood some ten or twelve inches off from the fire 
bed.) 

Deck passengers should not be allowed^o pile the wood 
on board the boat, especially after night, or in rough, 
cold, stormy weather, unless under the direction of 
the confidential hands belonging to the boat, to see 
that it be done with care. 

Another way in which steamers may have caught 
fire, is in shaking up the fires on the ©utside doors. 
The sparks are liable to fly back into the wood, and 
there lodge until the whole pile becomes ignited. Fire 
may also originate on low boiler decks from sparks, in 
the same way. The deck itself, when low, becomes 
greatly heated from the boilers, and would burn like a 
match if brought in contact with fire or sparks. 

Fire might originate in this Way : sometimes the 
tile or brick work between the boilers on top, may be- 
come wracked more or less from various causes, and 
the joints of the same may be open sufficiently to 
let heat enough escape to set fire to the deck. And 
it might be possible in some cases, especially if the 



1* HE PRACTICAL ENGINEER. 117 

brick work has not been well done ; or if some of the 
brick or tile were cracked when put in ; it might hap- 
pen that they would break to pieces and fall iuto the 
furnace sometime afterwards, without the knowledge 
of any one upon the boat. In this way the boat might 
be set on fire although the tile may have been put on 
double thickness, breaking joints at the same time. 

Another manner in which boats may have, and no 
doubt many have been set on fire, is by leaving can- 
dles burning in the state rooms, or down in the hold 
of the boat, where it may be near some combustible 
matter, where if it should gather a waster and run 
down, the wick might fall into spirits of turpentine; 
or the candle might emit sparks of fire, as they some* 
times do, especially if the wicks have been wet whilst 
being made, and thus set fire to combustable matter. 
Cases of this kind have occurred. If this be so, it Is 
dangerous to leave lights in any part of the boat, un- 
less there be some one present to use and attend to 
them while burning. In secret or retired places, such 
as the hold, berths, or any like localities, lights should 
not be allowed to remain burning, as they run the risk 
of setting the boat on fire, and also put in jeopardy 
the lives of all on board. 

Without detaining you any longer, by giving you 
further explanation on the subject of the various ways 
in which steamboats are liable to take fire, we will 



118 THE PRACTICAL ENGINEER. 

state to you how, in all probability, the Ben Sherod 
caught fire. It was in the night that she took fire, 
and it was said she had been running a race at the time 
with another boat and that they had been firing the 
boilers until they became red hot. Now, we do not 
believe the boilers were red hot, for such a thing is 
impossible if they had water up to the guage cocks, 
which we are inclined to think they had. It is very 
likely she took fire from the sparks flying, from shak- 
ing up the fires on the outside furnace doors, and these 
sparks of fire, no doubt, lodged and remained in 
among the cord wood until fanned into a flame by 
the running of the boat. 

Another way by which she may have caught fire, is 
that the brick work in the fire bed may have been 
worked partly down by the firemen, (this we have had 
done by firemen while running as engineer on the river, 
and therefore speak from experience, as well as obser- 
vation) and the fire bed being thin, would be very soon 
made red, and being red hot, would be very easely 
mistaken for the boilers being red hot. In this way, 
the wood along side of the fire bed may have taken 
fire, and been the cause of the burning of the boat and 
the loss of some 150 human beings. It was in the 
night, as before stated, and no doubt while many per- 
ished in the flames, many others were drowned in en- 
deavoring to make their way to the shore. 



THE PRACTICAL ENGINEER. 119 

The stsamer Ben Sherod was a very large and mag- 
nificent boat, commanded by Captain Russell during 
the time of this disaster. 

This would appear to be the way in which she took 
fire. Report says her boilers were made red hot. 
Now, we think it probable the brick work had been 
knocked down by the firemen while pushing the fires 
during the excitement of the race, and the fire bed be- 
coming red hot, would set fire to the wood at its side, 
and running against the wind, would instantaneously 
envelope the boat in flames. This may have been the 
very way in which this boat may have taken fire. 

We think this a proper occassion to suggest some 
ideas on the subject of guarding against fires, let them 
arise from what cause they may about the boilers. 
Boats which use wood for fuel, should have a bulk head 
in front of the wood, next the fire bed of the width of 
the wood pile. It should be lined with sheet iron to 
keep the sparks of fire from falling in among the wood 
while shaking up the fires. The fire bed should flare 
out considerably on top, so that the brick work at the 
fire end will not be so easily tumbled down by shaking 
up the fires. The tile, between and on top of the boil- 
ers, should be examined every now and then, to see 
that the joints are good, and the morter between the 
brick has not fallen out, so that heat and sparks may 
pass through them and set fire to the boat. Some line 



120 THE PRACTICAL ENGINEER, 

the under part of the boiler deck with sheet iron, and 
it being a non-conductor of heat, keeps the deck cooler 
than it would otherwise be ; and this may also be con- 
sidered a preventive against fire, which otherwise might 
be occasioned by sparks and heat from the opening in 
crevices of the brick work. These crevices and open- 
ings in the brick work on top and around the sides of 
the fire bed, should be examined and put in order every 
time the boat lays up to repair. 



DIFFERENT RULES FOR SQUARING AND 
LINING OF dHA*TS. 

Rule 1.— For squaring and lining of shafts, as used 
upon our steamers in early years, with one cylinder 
and four shafts — two main and two water wheel shafts; 
First— stretch a line through the center of the cylin- 
der timbers fore and aft with the boat ; then fit a flat 
piece of board between the cylinder timbers, even with 
the top of the timbers and at the center of the shafts ; 
then make a center point on this board for the tram- 
ble point at the center of the shafts, and also on the 
line passing through the center of the cylinder timbers 
and main wrist ; then take any distance you please on 
the trumbles — say 10 feet — and from the center of the 
shaft ; make a scribe or point from the shaft each way 



THE PRACTICAL ENGINEER. 121 

from the center, 10 feet each ; then from these two 
points on the straight line in the center of the cylinder 
timbers ; place the trambles and describe two circles 
that will intersect each other on the timber which is 
to receive the pillar block on which the end of the 
main shaft is to rest ; then stretch the line across the 
curves on these timbers, and this line for your shaft 
will be square with the center line through the cylin- 
der timbers. The next thing, then before laying out 
for your pillar blocks, is- to get the line for the shafts 
parallel, or at equal distances on both sides of the 
boat, with the shier plank, and then the shafts would 
be level when the boat is in trim. 

Rule 2. — How to square the shaft line to the cylin- 
der lines by figure : 6, 8 and 10, or any other num- 
bers, more or less, in the same proportion : Draw the 
center lines in the cylinder timbers, as in rule 1st, 
then make a mark on this line with a black lead pencil 
at the point where it is intended the center of the shaft 
is to come ; then measure 6 feet from this center, each 
way on your line, and mark these points with a black 
lead pencil ; then measure 8 feet each way from the 
center point, out from the center line, and then take 
a ten foot pole and try it to these points on the lines, 
and if they are- more or less than the pole, bring the 
shaft line round at either end, keeping the line to the 

center on the line fore and aft and when you get two 
11 



122 THE PRACTICAL ENGINEER. 

of these points to fit the length of the pole, the other 
three spaces will be the same length, and the lines will 
be square one with another. (The center line for the 
shafts will be equal, or parallel distances from the shier 
plank, as in rule first example for squaring of shafts. 
See plate. 

N. B. — Before the shafts are put into the pillar 
blocks, put a parallel straight edge accross the two 
main pillar blocks on the top of the bottom brasses, 
and then some 2, 3 or 4 feet aft of the slides, put on 
another parallel straight edge across the top of the cyl- 
inder timbers, and see if these straight edges are out 
of twist on top ; and if not, plain a narrow place across 
the top of the cylinder timbers until they are out 
of twist, and this place will be a guide, after the shafts 
are in their place, to put your slides and cylinder luge 
true, and level with the line through the center of the 
shaft. 

Rule 3. — How to line cylinders and square shafts 
for side-wheel boats, with double engines : When the 
cylinder timbers for both engines, are each one parallel 
from a line through the center of the boat, fore and 
aft, you will then stretch two center lines through the 
cylinder timbers parallel or equal distances with each 
other, — then stretch the center line for the shafts 
across these parallel lines where it is intended the cen- 
ter of the shafts are to come, and then proceed to 



THE PRACTICAL ENGINEER. 123 

square the shaft line with the cylinder line according 
to rule 1st, as laid down on page 120 or according to 
rule 2d, as found on page 121. 

Stern-wheel engines are squared in the same way as 
side wheel boat engines are, when the timbers of the 
side wheel boat are equal and parallel with each other 
but not otherwise. 

Rule 4. — How to square shafts with cylinder tim- 
bers, when the timbers are not parallel with each other, 
— We would here remark, that it is a common thing 
on side wheel boats with double engines, to have the 
cylinder timbers, at the water-wheel, something like 
six inches narrower then they are at the cylinder, 
sometimes more and sometimes less, as it may happen* 
We are opposed to this, for the following reason : The 
water wheels being turned several degrees out of square 
from a line drawn through the center of the boat, they 
will not pull straight ahead, but lose power in propor- 
tion to the number of degrees it is out of square. 

Whether this be done intentionally, by the ship car- 
penter, or not, we cannot at present say. But there 
are some who allege that it is better to be a little out 
of square, saying that it throws the water in on the 
rudder, thereby causing a stronger current against the 
rudder-blade ; there by enabling the pilot to steer the 
boat more easily. We have also heard that it was ad- 
vantageous in another respect. The boat is narrower 



124 THE PRACTICAL ENGINEER. 

at the stern, and the water being displaced by the 
wheel a little out of square, it is said causes the water 
displaced by the boat to return more rapidly to fill the 
vacancy, and that this acts upon the stern or narrow 
part of the boat in the same manner that any pressure 
would upon the narrow part of a wedge, thus assisting 
to propel the boat along. 

Our opinion is, notwithstanding these arguments, 
that the cylinder timbers should be parallel and the 
water wheel square with a line through the center of 
the boat ; and then, if the rudder is constructed as it 
should be, the boat will be easily stered without any 
additional assistance from the water wheels. 

But to square shafts with cylinder timbers that are not 
parallel with each other, a line must be drawn through 
each cylinder timber, and square each shaft from its 
own line, according to rule 1st, as laid down on page 
120, or, as rule 2d, page 121. 

Notwithstanding these two shaft lines are not straight 
with each other, sideways across the boat, (the cause 
of which is the cylinder timbers not being parallel 
with each other,) yet they would be and are straight the 
other way; the line being equal distances from the shier 
plank up. When relining shafts, after the boat has 
been running awhile, it may be that one or the other 
side of the boat has settled, sometimes an inch more 
or less. In lining the shafts in this case, it is not ne- 



THE PRACTICAL ENGINEER. 125 

cessary that they be equal distances from the shier 
plank, so that the centers of each shaft are at parallel 
distances from a line reaching across the boat which 
is parallel with the shier planks ; and the shaft can be 
squared by a line running through the cylinder ; this 
can be done by making a small center mark with a file 
or cold chisel on both sides of- the wrist in its center, 
and turning over and trying fore and aft on your line 
and keying your pillar blocks one way or other until 
both these marks fit the line which passes through the 
cylinder. 

For getting the shaft in line the other other way, or 
up and down : Stretch a line across the boat, from 
the center each way ; that is parallel from the shier 
planks, straight on top, though not straight side- 
ways. Let this line be some three, four, or five feet 
above the top of the journals or caps ; then take two 
small strips of wood, J or f inch square, and let there 
be a difference in the lengths of those strips equal to 
half the distance there is between the collar on the 
large journal and that of the smaller one; and then, 
if the long strip fits the collar on the small journal, 
and the short strip fits the collar on the large one, your 
shaft will be in line this way as well as the other. We 
suggest it as the easiest plan to measure from the tops 
of the collars, as it answers every purpose, and also 

saves the trouble of taking the caps off the tops of the 
11* 



126 THE PRACTICAL ENGINEER. 

pillar blocks which would be a great deal of unneces- 
sary trouble. 



BEST METHOD OF HOLDING BRACES IN 
WHEELS. 

Various methods have been tried to hold braces tight 
in water wheels, and very .expensive plans been devised 
for that purpose ; among others, that of a wrought 
iron flat band of large diameter, in two pieces, reach- 
ing to the outer braces near the edge of the inside 
buckets, ond these we believe were bolted fast both to 
the arms and to the braces. 

Another plan was to have two segments of flat iron, 
say two inches by half an inch, and equal in length to 
the distance of the arms on which they meet from cen- 
ter to center. These were bolted together by a great 
number of small bolts, and room enough left behind 
each arm for the purpose of tightening up the braces 
by driving in a wooden wedge. This was a very poor 
plan, as well as very expensive one. 

The best plan which has ever as yet been hit upon, 
and one which we believe admits of no rival, is that of 
a long bolt, fastened to the water wheel flange by an 
eye, a nut or a key, one which bolts passes through 
every set of braces in the wheel. On each bolt is a 



THE PRACTICAL ENGINEER. 127 

separate nut for the purpose of screwing down every 
brace in the wheel, and if there should be three, four, 
or more braces, there must be three, four, or more sizes 
of nuts, so that one will pass over the other ; and when 
these braces are screwed down tight, the braces in the 
water wheel arms will be as tight as a drum head. 



MILNER'S CUT-OFF VALVE GEAR. 

We think it proper to insert in this place a descrip- 
tion of Milner's Cut-off Cam Valve Gear, patented 
July 30th, 1850. The improvement consists in work- 
ing the steam valves by the combined action of two D 
cams ; I is the loose cam, with a segmental slot, and 
index plate on it ; the yoke of this cam is attached to 
the upper end of the oscillating bar N, by the connect- 
ing link 0, and the lower end of said bar is attached 
to the yoke of the fixed cam, in the same manner. 
The steam valves are operated from the center of the 
oscillating bar by the inside rod V. The fixed cam 
operates the exhaust valves as usual in other engines, 
and being attached by its yoke to the lower end of the 
oscillating bar, also opens the steam valves, as soon as 
the engine arrives at the point at which the engineer 
has set the loose cam I, to cut off steam ; it moves 
back the upper end of oscillating bar N, and cuts off 



128 THE PRACTICAL ENGINEER. 

steam. By slacking the screw and moving the loose 
cam to the figure at which it is desirable to cut off 
steam, it can be cut off at from one-eighth to to seven- 
eighths of the stroke with precision, enabling the engi- 
neer always to use all the steam he can make at any 
given pressure, and also to cut off at such a point, as 
to be able to keep steam without throttling it ; and as 
it is well known that boats on the Mississippi, with a 
load, and a head wind, cannot work off all their steam 
with these fixed cut-offs, nor supply steam to allow full 
strokes, they are obliged to lay to, or add pressure to 
their boilers to make headway. This invention, then, 
will add to the safety of boats and passengers ; for, by 
changing the cut-off, they can use all their steam and 
go ahead. Also, when running with fair wind, light 
load, and favorable tides, they cannot make steam 
enough, they are obliged to throttle it, and lose much 
of its elastic force. 

. This invention will be advantageous for light draught 
boats, and also for ships on a long voyage, requiring 
less weight of boiler and Fuel for a given power. Ex- 
ample — A boat now running with two cylinders of fif- 
teen inch diameter, and two boilers doubled-flued, forty 
inches, and cutting off steam at three-fourths of the 
stroke, would run quite as fast, with one boiler, if the 
cylinders were twenty and a half inches, and steam 
cut off at one-fifth of the stroke. Again : the two 



THE PRACTICAL ENGINEER. 129 

boilers would supply cylinders of twenty-nine and a 
half inches, cut off at one-fifth stroke, and would very 
nearly double the power, with very little additional 
weight, and no more fuel. 

Again : this improvement recommends itself to en- 
gineers and steamboat owners by its simplicity and 
easy construction ; also by its durability. Cut-off 
cams for half-stroke even, are soon worn out, and are 
a continual cost to engines, whereas, these D cams will 
answer the purpose to cut off at any point, and are not 
subject to wear out, as the pointed cams are ; they 
can also be so altered as to suit any change of fuel, 
from good to bad, and vice versa ; or in case of a want 
of fuel, to use what they' have to the best advantage. 



130 



THE PRACTICAL ENGINEER. 



AREAS OF CIRCLES, FROM 1 TO 100. 



i 

6T 

1 

1 

Y 

8 
3 

¥ 

4 
5 

Y 

8 

7 

¥ 

9 

T6" 

5. 

A 
V s 

4 
13 

¥ 

8' 
15 
T6 



Area. | 


Diam. 


Area 


Diam. 


Area. 


Diam 

12. 


.00019, 


■i 


8.295 


•f 


45.663 


.00076 


•1 


8.946 


■I 


47.173 


4 


.00306 


■i 


9.621 


■i 


48.707 


$ 


.01227 


■1 


10.320 


8. 


50.265 


•1 


.02761, 


4 


11.044 


■i 


51.848 


•* 


.04908, 


■i 


11.793 


•i 


53.456 


;t 


.07669 


4. 


12.566 


•I 


55.088 


•i 


.1104 


■i 


13.364 


■i 


56.745 


4 


.1503 


■i 


14.186 


•1 


58.426 


13. 


.1963 




15.033 


•I 


60.132 


•J 


.2485 


% 


15.904 


•I 


61.862 


•4: 


.3067 


5 

•8 


16.800 


9. 


63.617 


•t 


.3712 


•1 


17.720 


■i 


65.396 


•i 


.4417 


s 


18.665 


■i 


67.200 


•l 


.5184 


5. 


19.635 


•1 


69.029 


'I 


.6013 


4 


20.629 


■i 


70.882 


■l 


.6902 


.* 


21.647 




72.759 


14. 


.7854 


•1 


22.690 


•f 


74.662 


4 


.9940 


•i 


23.758 


■i 


76.588 


■i 


1.227 


i 


24.850 


10. 


78.539 


•1 


1.484 




25.967 


■i 


80.515 


1 


1.767 


i 


27.108 


■i 


82.516 


■1 


2.073 


6. 


28.274 


•1 


84.540 


•S 


2.405 


•* 


29.464 


■i 


86.590 


•J 


2.761 


a 


30.679 


s 

•8 


88.664 


15. 


3.141 


•t 


31.919 


•I 


90,762 


-i 


3.546 


4 


33.183 


•J 


92.885 


•i 


3.976 


4 


34.471 


11. 


95.033 


•1 


4.430 


*4 


35.784 


■i 


97.205 


•1 


4.908 


•i 


37.122 


■i 


99.402 


•f 


5.411 


7. 


38.484 


■t 


101.62 


•1 


5.939 


•* 


39.871 


■i 


103.86 


1 


6.491 


•i 


41.282 


.1 


106.13 


16. 


7.068 


•t 


42.718 


•8 


108.43 


« 


7.669 


■4 


44.178 


•J 


110.75 


■i 



THE PEACTICAL ENGINEER. 



131 



TABLE— (Continued.) 



Diam 


Area. 


Diam. 


Area. 


Diam. 


Area. 


Diam. 


Area. 


•t 


210.59 


21. 


346.36 


■1 


515.72 


'1 


718.69 


■i 


213.82 


•4 


350.49 


•s 


520.70 


4 


724.64 


•f 


217.07 


■i 


354.65 


•4 


525.83 


•i 


730.61 


•i 


220.35 


•1 


358.84 


26. 


530.93 


4 


736.61 


•i 


223.65 


•4 


363.05 


•4 


536.04 


•1 


742.63 


17. 


226.98 


5 


367.28 


•4 


541.18 


4 


748.69 


.* 


230.33 


4 


371.54 


•f 


546.35 


31. 


754.76 


•i 


233.70 


■l 


375.82 


•4 


551.54 


•ft 


760.86 


•1 


237.10 


22. 


380.13 


•f 


556.76 


•4 


866.99 


•4 


240.52 


* 


384.46 


•8 


562.00 


•t 


773.14 


•f 


243.97 


■i 


388.82 


•4 


567.26 


i 


779.31 


•s 


247.45 


•f 


393.20 


27. 


572.55 


4 


785.51 


•i 


250.94 


4 


397.60 


•4 


577.87 


•S 


791.73 


18. 


254.46 


•i 


402.03 


•4 


583.20 


4 


797.97 


•4 


258.01 


a 

•4 


406.49 


•1 


588.57 


32. 


804.24 


•i 


261.58 


■i 


410.97 


•4 


593.95 


•i 


810.54 


•1 


265.18 


23. 


415.47 


4 


599.37 


•i 


816.86 


•4 


268.80 


■4 


420.00 


4 


604.80 


•1 


823.21 


•1 


272.44 


•4 


424.55 


* 


610.26 


4 


829.57 


•4 


276.11 


•1 


429.13 


28. 


615.75 


4 


835.97 


* 


279.81 


•J 


433.73 


•4 


621.26 


•i 


842.39 


19. 


283.52 


•1 


438.30 


•4 


626.79 


** 


848.83 


•4 


287.27 


•1 


443.01 


■I 


632.35 


33. 


855.30 


•4 


291.03 


■I 


447.69 


•4 


637.94 


•i 


861.75 


•1 


294.83 


24. 


452.39 


4 


643.54 


■4 


868.30 


•4 


298.64 


•4 


457.11 


•I 


649.18 


•1 


874.84 


•f 


302.48 


•4 


461.86 


■i 


654.83 


•J 


881.41 


■1 


306.35 


•f 


466.63 


29. 


660.52 


■1 


888.00 


•I 


310.24 


•4 


471.43 


•4 


666.22 


•f 


894.61 


20. 


314.16 




476.25 


•4 


671.95 


4 


901.25 


•1 


318.09 


■I 


481.10 


3 


677.71 


34. 


907.92 


■i 


322.06 


•4 


485.97 


4 


683.49 


■* 


914.61 


•s 


326.05 


25. 


490.87 


4 


689.29 


•4 


921.32 


•4 


330.06 


•J 


495.79 


•4 


695.12 


•§ 


928.06 


•1 


334.10 


•4 


500.74 


i 


700.98 


4 


934.82 


■% 


338.16 




505.71 


30. 


706.86 


4 


941.60 


•4 


342.25 


•4 


510.70 


•t 


712.76 


•f 


948.41 



132 



THE PRACTICAL E N a I N E E ft 



TABLE— (Continued.) 



Diam. 


Area. 


Diam. 


Area. 


Diam. 


Area. 


Diam. 


Area. 


•"8" 


955.25 


1 


1225.4 


•8 


1529.1 


3 

•4 


1866.5 


35. 


962.11 


5 

• 8 


1233.1 


1 
•4 


1537.8 


7 

•8 


1876.1 


4 


968.99 


3 
•4 


1240.9 


3 

•8 


1546.5 


49. 


1885.7 


•i 

3 

•8 

■* 

•f 
•8 

,1 


975.90 


7 

•8 


1248.7 


l 
•2 


1555.2 


i 

•8 


1895.3 


982.84 


40. 


1256.6 


5 

• 8 


1564.0 


1 

•4 


1905.0 


989.80 


i 

•8 


1264.5 


3 

•4 


1572.8 


3 

• 8 


1914.7 


996.78 


1 

•4 


1272.3 


7 

•8 


1581.6 


1 
•2 


1924.4 


1003.7 


3 

•8 


1280.3 


45. 


1590.4 


.1 


1934.1 


1010.8 


1 
•2 


1288.2 


i 

•8 


1599.2 


3 

•4 


1943.9 


* 8 

36. 


1017.8 


5 
•8 


1296.2 


1 
•4 


1608.1 


7 

•8 


1953.6 


■i 


1024.9 


3 

•4 


1304.2 


3 

•8 


1617.0 


50. 


1963.5 


1032.0 


7 

•8 


1312.2 


l 
•2 


1625.9 


i 

•8 


1973.3 


*4 

•f 
■i 

4 
•I 

■i 

37. 


1039.1 


41. 


1320.2 


5 

•8 


1634.9 


1 
•4 


1983.1 


1046.3 


i 

• 8 


1328.3 


3 

• 4 


1643.8 


3 

•8 


1993.0 


1053.5 


1 

•4 


1336.4 


7 

•8 


1652.8 


1 

•2 


2002.9 


1060.7 


3 

• 8 


1344.5 


46. 


1661.9 


5 
• 8 


2012.8 


1067.9 


1 
• 2 


1352.6 


i 

• 8 


1670.9 


2. 
•4 


2022.8 


1075.2 


5 
• 8 


1360.8 


•4 


1680.0 


7 

•3 


2032.8 


■i 
■i 
•t 
•i 

5 


1082.4 


3 
• 4 


1369.0 


3 

•8 


1689.1 


51. 


2042.8 


1089.7 


7 
•8 


1377.2 


1 
• 2 


1698.2 


i 

•8 


2052.8 


1097.1 


42. 


1385.4 


.1 


1707.3 


1 

•4 


2062.9 


1104.4 


i 

•8 


1393.7 


3 
.4 


1716.5 


4 


2072.9 


1111.8 


.i 


1401.9 


7 
•8 


1725.7 


4 


2083.0 


•8 


1119.2 


3 

• 8 


1410.2 


47. 


1734.9 


5 

• 8 


2093.2 


7 


1126.6 


1 

■2 


1418.6 




1744 1 


3 

•4 


2103.3 


38. 


1134.1 


5 
•8 


1426.9 


1 

• 4 


1753.4 


7 

•8 


2113.5 


x 


1141.5 


3 

.4 


1435.3 


3 

• 8 


1762.7 


52. 


2123.7 


• 8 

1 

•4 

.3 


1149.0 


7 

•8 


1443.7 


• 2 


1772 


•8 


2133.9 


1156.6 


43. 


1452.2 


5 
• 8 


1781 3 


.i 


2144.1 


• 8 
l 

•2 

5 
•8 

•4 
7 


1164.1 


•8 


1460.6 


3 
• 4 


1790.7 


3 

• 8 


2154.4 


1171.7 


1 

•4 


1469.1 


7 

•8 


1800 1 


1 
• 2 


2164.7 


1179.3 


3 
•8 


1477.6 


48. 


1809.5 


5 
• 8 


2175.0 


1186.9 


I 
• 2 


1486.1 




1818.9 


3 

•4" 


2185.4 


•8 

39. 


1194.5 


5 
• 8 


1494.7 


1 

•4 


1828*4 


7 
•8 


2195.7 


i 


1202.2 


3 
• 4 


1503.3 


3 

• 8 


1837*9 


53. 


2206.1 


• 8 


1209 9 


7 

. 3 


1511.9 


1 


1847 4 


1 

•8 


2116.6 


• 4 


1217.6 


44. 


1520.5 


5 


1856 9 


1 
•4 


2227.0 



THE PRACTICAL ENGINEER. 



133 



TABLE— (Continued.) 



Diam. 


Area. 


Diam. 


Area. 


Diam. 


Area. 


1 Diam. 


Area 


•f 


2237.5 


58. 


2642.0 


i 


3080.2 


4 


3552.0 


1 


2248.0 


■i 


2653.4 


I 


3092.5 


3 


3565.2 


1 


2258.5 


•i 


2664.9 


•j 


3104.8 


■A 


3578.4 


•I 


2269.0 


3 

•8 


2676.3 


63. 


3117.2 


•f 


3591.7 


•i 


2279.6 


4 


2687.8 


i 


3129.6 


•S 


3605.0 


54. 


2290.2 


5 
•8 


2699.3 


i 

•4 


3142.0 


7 
"8 


3618.3 


■i 


2300.8 


■i 


2710.8 


•i 


3154.4 


68. 


3631.6 


■i 


2311.4 


7 


2722.4 


■i 


3166.9 


•i 


3645.0 


■i 


2322.1 


59. 


2733.9 


5 

•8 


3179.4 


i 

•4 


3658.4 


■i 


2332.8 


4 


2745.5 


•I 


3191.9 


1 -1 


3671.8 


4 


2343.5 


$ 


2757.1 


■i 


3204.4 


i 4 


3685.2 


•I 


2354.2 


3 

*8 


2768.8 


64. 


3216.9 


i 4 


3698.7 


■i 


2365.0 


•J 


2780.5 


■i 


3229.5 


I •£ 


3712.2 


55. 


2375.8 


•f 


2792.2 


■i 


3242.1 


! -J 


3725.7 


■i 


2386.6 


3 

'4 


2803.9 


3 

•8 


3254.8 


69. 


3739.2 


■i 


2397.4 


7 
•8 


2815.6 


■i 


3267.4 


•i 


3752.8 


•t 


2408.3 


60. 


2827.4 


4 


3280.1! 


i 

'4 


3766.4 


■i 


2419.2 


i 


2839.2 


•1 


3292.8 


3 

•8" 


3780.0 


4 


2430.1 


i 


2851.0 


4 


3305.5 ! 


3 


3793.6 


•1 


2441.0 


■t 


2862.8 


65. 


3318.3 


•1 


3807.3 


S 


2452.0 


£ 


2874.7 


•i 


3331.0 j 


•1 


3821.0 


56. 


2463.0 


4 


2886.6 


•i 


3343.0 


| 


3834.7 


■i 


2474.0 


•i 


2898.5 


4 


3356.7 j 


70. 


3848.4 


■i 


2485.0 


•j 


2910.5 


4 


3369.5 


a 


3862.2 


3 

•8 


2496.1 


61- 


2922.4 


4 


3382.4 ! 


•i 


3875.9 


i 


2507.1 


A 


2934.4 


•f 


3395.3 


3 

•8" 


3889.8 




2518.2 


4 


2946.4 


4 


3408.2 ; 


J 


3903.6 


1 


2529.4 


•i 


2958.5 


66. 


342 1.2 i 




3917.4 


•i 


2540.5 


•i 


2970.5 


4 


3434.1 | 


*4 


3931.3 


57. 


2551.7 


■s 


2982.6 


■i 


3447.1 ! 


•J 


3945.2 


4 


2562.9 


■i 


2994.7 


•1 


3460.1 


71. 


3959.2 


4 


2574.1 


7 
•8" 


3006.9 


4 


3473.2 


A 


3973.1 


•1 


2585.4 


62. 


3019.0 


4 


3486.3 ! 


4 


3987.1 


•I 


2596.7 


*l 


3031.2 


•1 


3499.3 


•t 


4001.1 


4 


2608.0 


£ 


3043.4 


4 


3512.5 


4 


4015.1 


•8 


2619.3 


•t 


3055.7 


67. 


3525.6 


| 


4029.2 


•J 


2630.7 


.J | 3067.9 ) 


A 


3538.8 


•1 


4043.2 




12 















1M 


THE 


PRACTICAL ENGINEER, 






TABLE— (Continued.) 




Diam.l 


Area. 


Diam. 


Area. 


Diam. 


Area. 


Diam. 


Area. 


•* 


4067.3 


1 

•2 


4596.3 


1 
•8 


5168.9 


3 


5775.0 


72. 


4071.5 


5 
• 8 


4611.3 


1 
-4 


5184.8 


>8 


5791.9 


i 


4085.6 


3 

•4 


4626.4 


3 

• 8 


5200.8 


86. 


5808.8 


>i 


4099.8 


7 

•8 


4641.5 


l 
°2 


5216.8 


1 

•8 


5825.7 


•t 


4114.0 


77. 


4656.6 


5 

• 8 


5232.8 


1 
•4 


5842.6 


•4 


4128.2 


i 

•8 


4671.7 


3 
-4 


5248.8 


3 

•8 


5859.5 


4 


4142.5 


I 
•4 


4686.9 


7 

•8 


5264.9 


1 
•2 


5876.5 


•1 


4156.7 


•# 


4702-1 


82. 


5281.0 


•f 


5893.5 


•1 


4171.0 


1 
• 2 


4717.3 


i 

•8 


5297.1 


3 

•4 


5910.5 


73. 


4185.3 


5 
• 8 


4732.5 


1 

•4 


5313.2 


7 
•8 


5927.6 


-* 


4199.7 


3 

•4 


4747.7 


3- 
•8 


5329.4 


87. 


5944.6 


•i 


4214.1 


7 

•8 


4763.0 


1 

•2 


5345.6 


1 

• 8 


5961.7 


3 
•8 


4228-5 


78. 


4778.3 


5 
• 8 


5361.8 


1 
•4 


5978.9 


* 


4242.9 


i 

.8 


4793.7 


3 
•4 


5378.0 


3 

•8 


5996.0 


•1 


4257.3 


i 

•4 


4809.0 


7 
•8 


5394.3 


•2 


6013.2 


•1 


4271.8 


3 

• 8 


4824.4 


83. 


5410.6 


J 


6030.4 


«* 


4286.3 


• 2 


4839.8 


i 

•8 


5426.9 


3 

• 4 


6047.6 


74. 


4300.8 


5 
• 8 


4855.2 


1 
•4 


5443.2 


7 
•8 


6064.8 


•J 


4315.3 


3 
• 4 


4870.7 


3 

•8 


5459-6 


88. 


6082.1 


•i 


4329.9 


7 

•8 


4886.1 


•2 


5476-0 


.1 


6099.4 


•1 


4344.5 


79. 


4901.6 


5 
• 8 


5492-4 


1 
•4 


6116.7 


•4 


4359.1 


•8 


4917.2 


3 

• 4 


5508.8 


.1 


6134.0 


4 


4373.8 


.i 


4932.7 


7- 

•8 


5525.3 


•4 


6151.4 


4 


4388.4 


3 

• 8 


4948.3 


84. 


5541.7 


5 

• 8 


6168.8 


7 

•8 


4403.1 


l 

•2 


4963.9 


•8 


5558.2 


3 

•4 


6186.2 


75. 


4417.8 


5 
• 8 


4979.5 


.i 


5574.8 


7 

•8 


6203.6 


•5 


4432.6 


3 

• 4 


4995.1 


3 

•8 


5591.3 


89. 


6221.1 


i 
■4" 


4447.3 


7 

• 8 


5010.8 


l 
•2 


5607.9 


1 

• 8 


6238.6 


3 

•8 


4462.1 


80. 


5026.5 


5 

• 8 


5624.5 


1 

• 4 


6256.1 


1 

•2 


4476.9 


i 

• 8 


5042.2 


3 
• 4 


5641.1 


3 

•8 


6273.6 


5 


4491.8 


1 
•4 


5058.0 


7 

•8 


5657.8 


1 
• 2 


6291.2 


3 

♦ 5 


4506.6 


3 


5073.7 


85. 


5674.5 


.1 


6308.8 


7 

•8 


4521.5 


• 2 


5089.5 


.1 


5691.2 


3 

•4 


6326.4 


76. 


4536.4 


5 
.8 


5105-4 


i 

•-4 


5707.9 


7 

•8 


6344.0 


.* 


4551-4 


3 
• 4 


5121.2 


3 

-8 


5724.6 


90. 


6361.7 


i 

• 4 


4566.3 


7 

• 8 


5137.1 


•2 


5741.4 


A 
• 8 


6379.4 


.1 


4581.3 


81. 


5153.0 


•# 


5758.2 


1 
•4" 


6397.1 



THE PRACTICAL ENGINEER. 135 

TABLE— (Continued.) 



Diameter 


Area. 

6414.8 


Diam. ' 

■i 


Area " 


Diam. 

3 

•8 


Area. 


Diam. 
•* 


Area 


4 


6776.4 


7144.3 


7523.7 


4 


6432.6 


93. 


6792.9 


■i 


7163.0 


98. 


7542.9 


4 


6450.4 


■i 


6811.1 


4 


7181.8 


i 


7562.2 


I 


6468.2 


'4 


6829.4 


3 

'4 


7200.5 


i 

•4 


7581.5 


7 
•"ff 


6486.0 


3 

•8 


6847.8 


7 
•8 


7219.4 


•t 


7600.8 


91. 


6503.8 


4 


6866.1 


96. 


7238.2 


4 


7620.1 


* 


6521.7 


5 

•8 


6884.5 


■i 


7257.1 


4 


7639.4 


♦4 


6539.6 


•I 


6902.9 


i 

•4 


7275.9 


•1 


7658.8 


•1 


6557.6 


■i 


6921.3 


•1 


7294.9 


$ 


7678.2 


i 


6575.5 


94- 


6939.7 


■i 


7313.8 


99. 


7697.7 


•1 


6593.5 


•i 


6958.2 


•1 


7332.8 


'$ 


7717.1 


•I 


6611.5 


■i 


6976.7 


•3 


7351.7 


i 

'4 


7736.6 


•5 


6629.5 


3 

•8 


6995.2 


7 
•8 


7370.7 


•1 


7756.1 


92. 


6647.6 


4 


7013.8 


97. 


7389.8 


■4 


7775.6 


■i 


6665.7 


•f 


7032.3 


* 


7408.8 


5 

•8 


7795.2 


4 


6683.8 


3 

"4 


7050.9 


-i 


7427.9 


•i 


7814.7 


•t 


6701.9 


•f 


7069.5 


•t 


7447.0 


•i 


7834.3 


•4 


6720.0 


95- 


7088.2 


•4 


7466.2 


100. 


7853.9 


•f 


6738.2 


•* 


71069 


■« 


7485.3 






•t 


6756.4 


_•* 


7125.5 


*4 


7504.5 







136 THE PRACTICAL ENGINEER. 



TO FIND THE WEIGHT OF STEAM CARRIED 
IN THE BOILER. 

We will make some explanatory remarks on this 
subject before we proceed to lay down the rule. 

There are of a circle whose diameter is 1. is a deci- 
mal .7854, &c. 

In the first place, it will be necessary to show how 
notches in the safety lever should be laid off system- 
atically, and not at random. The distances of the 
notches on the safety valve lever, from center to cen- 
ter, should always be equal to the distance of the two 
bolt or pin holes in the end of the safety valve lever, 
which holes are used, the one to support the lever 
in the stand, and the other to connect the valve stem 
to the safety valve lever. And let it be always un- 
derstood, that the first notch from the valve stem 
counts two, for this reason : it is twice the distance 
from the center of the stand in which the safety valve 
lever is suspended to the first notch in the lever, that 
it is from notch to notch ; or from the center of the 
safety valve stem, where it is fastened to the lever, to 
the center of the bolt in the end of the lever, by which 



THE PRACTICAL ENGINEER. 137 

It is fastened to the stand or column, it is equal to one 
notch. Again; the distance from the center of the 
safety valve stem to the center of the first notch on 
the lever is equal to another notch, and these two dis- 
tances are from the center of the valve stem each way 
equal, and are each when added together two distances. 
This is the reason why the first notch on the safty 
valve lever requires to be doubled. Another mode is : 
suppose the weight on the end of the lever to be taken 
off and placed on top of the safety valve. This is 
equal to one notch ; now suppose we were to have 12 
notches in the lever, instead of putting the weight out 
12 notches, which makes it equal to 12 weights of the 
same weight, just place 12 weights, one on top of the 
other on the safty valve, which is equal to the weight 
of 12 notches out on the lever. This is another reason 
why the first notch on the lever counts two, or is to 
be doubled. 

The next thing now will be to ascertain the nett 
amount of weight there is on the safety valve seat from 
the weight of the safety valve, lever, valve stem, 
valve, &c. This is done by means of a pair of steel- 
yards or spring scales, by being hooked to a string 
fastened to the lever at the center of the safety valve 
stem. 

(See draft in which the safety valve calculations 

are made.) 
12* 



138 THE PRACTICAL ENGINEER. 

The next and last thing, is to get the number of 
pounds the pea on the safety valve lever weighs. Mul- 
tiply the weight of the pea by the number of notches 
in the safety lever, always bearing in mind to count 
the first notch two. You then divide this amount of 
pounds by the number of square inches in the safety 
valve seat, and the product will be the amount of 
pressure of steam you are carrying in the boiler, with 
the weight of the pea, and to this you add the addi- 
tional weight caused by the lever, valve stem, valve, 
&c, and those two products, added together, will be 
the exact weight of steam carried in the boiler. 

Example 1. — The opening in the safety valve seat is 
3 inches in diameter, the pea is 50 pounds, and there 
are 8 notches in the lever, counting the first notch 2 ; 
what is the weight of steam per square inch ? 

3 
3 

9 
.7854 a decimal. 



7.0686 Product of the multiplication of 7 

square inches in the safety valve seat. 

Multiply a 50 pound pea by 8 notches and divide 

by 7 the number of square inches in the safety valve 

seat, and the product will be the weight of steam in 

the boilers produced by the weight of the pea on the 



THE PRACTICAL ENGINEER. 139 

end of the lever ; to this you add the additional weight 
caused by the lever, valve, valve stem, &c. 

50 lbs. 
8 notches. 

Divide by 7 square \ 7)400 lbs. 

inches in valve seat. / 

57^ lbs. per square inch. 
3 

60J lbs. of steam per square 
inch. 

Suppose the lever and rigging to weigh at the cen- 
ter of the valve stem 21 pounds, which, divided by the 
number of square inches in valve seat, which is 
7 ) 21 lbs. 

3 lbs. to the square inch to be 

added for the lever, valve and valve stem. 

Example 2. — Suppose the opening in the safety 

valve seat to be 4 inches in diameter, the weight of 

the pea 100 pounds, and 12 notches in the lever, 

(counting the first notch two,) what is the height of 

the steam in the boiler ? 

Decimals .7854 

16 is the square of 4. 



4.7124 

7.854 



12.5664 Product of the multiplication. 



140 THE PRACTICAL ENGINEER. 

In order to divide 12J inches into 1200 lbs., botl 
must be brought into halves. 

Pea 100 lbs. 

12 notches in the lever. 

1200 lbs. to be divided by 12J 

square inches in the safety valve seat. 

12J inches. 
2 1200 lbs. 

— 2 

225 96 lbs. of sleam per square inch. 






150 
150 

To which is to be added the extra weight of safety 

valve, lever, valve, valve stem, &c, which we suppose 

to weigh 50 lbs., and which is to be divided by the 

number of square inches in the safety valve seat, which 

is 12J square inches to be divided into 50 lbs. 

121 50 lbs. 
2 2 

25 ) 100 ( 4 lbs. to the square inch is 
100 the additional weight of the 

lever, valve, valve stem, &c, which are to be added to 
the weight produced by the pea on the safty valve le- 
ver, which is 96 lbs. to the square inch, and 4 lbs. ad- 
ded makes 100 lbs. of steam to the square inch. 
How to find the weight of steam you are carrying 



THE PRACTICAL ENGINEER 



141 



on each notch of the safety valve lever : In a 4 inch 
valve seat there is 12J square inches, and that multi- 
plied by 8 makes 100 ; therefore, every 8 lbs. of 100 
pea is the weight on each square inch of 12 inches of 
the opening, making 96 pounds ; and the remaing 4 
pounds of the 100 pounds pea, being the half of 8 lbs. 
is the weight on the remaining J- inch of the opening 
of 12.5 area. Now when 100 pounds pea is on the 
end of the safety valve lever, it gives 96 pounds of 
steam to the square inch on the safety valve ; to this 
you have to add the additional weight caused by the 
safety valve lever, valve and valve stem, which is 4 lbs. 
to the square inch, as shown in example 2. 

Weight of steam with the To this add 4 lbs. for the 
pea on the first notch is 
equal to 

1st notch 8 lbs. 
2nd 16 

3d... 
4th . . 



5th 

6th 

7th 

8th 

9th 

10th 

11th 

12th 



,24 
.32 
.40 
.48 
M 
.64 
,72 
.80 
.88 
.96 



weight of lever, valve, 
valve stem, &c. 

4 lbs. 12 lbs. on first notch. 

20 " " 

28 " " 

36 " " 

44 " " 

52 " " 

60 " " 

68 " " 

76 " " 

84 " " 

92 " " 
100 do. lbs. of steam to 



the square inch with the pea on the 12th notch. 



142 THE PRACTICAL ENGINEER. 

Example 3. — The diameter of the safety valve is 
5 inches ; the pea is 140 pounds ; there is 12 notches 
on the lever, counting the valve stem one and the next 
notch 2 ; the weight of the valve, the stem, and the le- 
ver, weighs, through the hole in the lever at the center 
of the valve stem, 60 lbs, what is the pressure of steam 
carried in the boiler ? 



5 inches diameter of valve seat. 
5 

25 square. 

7854 


39.270 

15.708 



19.6350 
Lever &c, 60 lbs., to be divided by 19 inches and 



6-10 of an inch : 



19.6 60 lbs. 

10 10 

166 )600(3A 

588 



) 12 (T9 



4 f 

196 



THE PRACTICAL ENGINEER. 



148 



140 lbs. weight of pea. 
12 notches. 



1680 lbs. to be divided 


by 


19.6 tenths of an inch. 


10 1680 


10 


196 


196)16800 (85 4- 


1568 


I % A 


1120 


980 


) 140 5 


28 V 


— are 88 }J lbs. 


J 196 


7 of steam pres- 


sure to the square inch in the boiler. 





144 THE PRACTICAL ENGINEER. 



PUPPET AND BALANCE VALVE ENGINE. 

We would suggest an idea for the reflection and con- 
sideration of those whom it may concern, about the 
propriety of having the valve seats, into which they 
have to bed themselves on a dead level while the engine 
itself is on an incline plane. The valves falling into 
seats on an incline has a tendency to fall or bear hard 
on the lower side of the seat, while it is possible in 
some cases for the valve to be open on the high side 
of the seat, as the valve, owing to the incline of the 
seat and weight of the lever, inclines to slide down- 
wards. Therefore we would suggest as the best, most 
natural, and only true plan for working puppet en- 
gines, is to have the valve seat on a dead level. 





Scale . 
2 


3. 


, 


i 


1, 








Diajn eter 
of Valve. 


LxreumfeiVi.. 

ofOp. 


.Areee 
of Op. 


J 


4- tz 










1. 


3.1 U 


7854- 


12752 




3. 


9kZ 


706 


1Wt8 


/4. 


H- 


ton 


8.29 


1Z.056 


2? 


H- 


10,99 | 


9.62 


16J9k 


10. 


?3 


11.18 


11.9b 


9.055 


9>i 


' 


1ZM 


nj6 


7,958 | 


k 


4 


13.35 


WJ8 


7.050 


7. 


H 


1b.13 


15.90 


6.288 


6. 




Vt.92 


17*72 


5.6*3 


-5 

5X 


* 

![ - 


1570 


1963 


5093 


5. 1 


Olf- 


16M 


Z16i 


Z.6Z9 


*-| 


■H 


mt 


23.75 


k.ZOS 


4t\ 


H- 


18.06 

1 


Zj.96 


3.851 


3 


6 


18M 


18.27 


3.537 


3., 



Thi* table gives Ihe weight ofSlrcarr^ ccuv 
ofllie SafteyYalie leaver: Valve <£Va7>ve s 




H 



n. 



10.99 



9.62 



11.18 



1256. 



13.35 



H I MM 



*± 



14.92 



15.70 



11.94 



12.56 



14,18 



15.90 



1772 



■*■ 



1963 



■H 



17.21 



23.75 



18.06 



M.96 



18M 



18. 27 



10.394 



9.035 



7.M8 



1.030 



6.288 



3.6*3 



5093 



4.620 



4-209 



3.851 
3.537 



41.6 



60.3 | 72.3 

I 

52.0 I 62.lt n.8 83.2 ! 93.5 



84.4 96. 

I 



108.5 | 120.6\ /JZ.O 



10.4 \ 208 \ 31.2 

9.1 j 18.1 m I 362 j 45.3 | 54.3 j 63.4 12,4 81.5 



B.0 1S..9 | 23,9 ; 31.8 j 3S.8 \ 47.7 j 55.7 \ 637 71.6 
7.0 14-.1 21,1 I 28.2 \ 352 \ 41.5 



63 



12.6 



18.9 | 25.2 



31. k 317. 



49.3 



36. U ! 63, 



50.3 



5.6 i 11.3 169 \ 22.6. j 28.2 j 33.9 35,5 



1o\2 



13.3 



20J, 



45. 1 



4.0 j 9.2 



13,9 j 18.5 



4.2 



8.4 12.6 16.8 



3.9 
3,5 



7.7 \ 11.6 I 1£* ! 
^7~T 10.6 I 14$ j 17.1 j 21.1 



23.5 ! 30.6 ! 35.7 40 g 

23.1 27.1 \ 32.3 ' 

21.0 25.2 295 33.7 

19.3 I 231 \ no 



56.6 



50.8 



65.8 



: ] 

37.0 4-1.6 



103.0 | 114.3 
90.5 I 09.6 



14t7. 

124.7 
108.7 



78.6 I 81.5 , 95J 



10.5 77.5 



6?£ 69.2 



56.4 



50J 



62.1 



15.5 



61.4 



56.0 I 61.1 



46.2 \ 50,8 j 55.4 



U2.1 j 46.3 \ 50.5 



30.8 \ 34.1. I 38.5 \ 41.4 \ 56.6 



24- 



28.3 j 31i 



35.5 \ 38.4 



42A | 



•It 



b 

si 



? * I 






KS. 



iki.uk* ^esthene^tofSU^earrrect.vrTI, upea <*H,e1eav e r of 1 01216,. exclusive of the « <J,W, °*f "^ 
rfihc SafteyYaZv* leaver: Valve Waive stem, tins aMttional weigU «* * aat 6v «,p«*r of Steel v«vJ sash e, e ia,d 



THE PRACTICAL ENGINEER. 145 



TO PRACTICAL ENGINEERS. 

This table is intended for the benefit of those who 
have not been sufficiently educated for the ascertain- 
ing, by calculation, the weight of steam they are car- 
rying. It is well known that there are many skilful, 
trusty, and confidential engineers, whose perseverance 
and attention to duty have won for themselves the 
confidence of those by whom they are employed, and 
have elevated themselves to high standing as engi- 
neers, worthy of all trust, but who suffer from an im- 
perfect knowledge of the principles upon which the 
safety valve calculations are made. 

To this class of engineers, this table is intended, 
merely as a substitute for the advantages of an educa- 
tion, and will be found to contain all the necessary 
matter relative to making safety valve calculations of 
interest or importance to the practical engineer. And 
in addition to these calculations, to the uneducated en- 
gineers other considerations attach great importance to 
the tables and scales, of steam pressure and tempera- 
ture in his hands ; as they not only supply him with 
all necessary and useful imformation as to the state of 
steamintheboilersand at all times operating as a safe- 
ty guard against explosions — but they also afford him 
13 



146 THE PRACTICAL EtfaiSTEEll, 

a personal protection from any enactment by law with 
regard to bis proficiency, as a practising engineer, re- 
quiring a qualification, which f in the absence of the 
safety valve calculator, could not Be attained without 
the aid of an arithmetical calculation. As the chief 
object of this table is for the benefit and protection of 
the practical engineer alone y and to assist him in the 
attainment of useful knowledge in his business, it is 
hoped it will be cheerfully received by that class of 
men for whom it is designed. 



THE PBACTICAL ENGINEER. 147 

THE USE OF THE TABLE EXPLAINED. 

Scale 1st gives the diameter of the opening in the 
safety valve seats. 2d — gives the circumference of 
the opening in seats. 3d — the area of the openings, 
4th — contains the relative amounts in steam pressure 
to the square inch in steam as the load on the safety 
valve, for every notch that a pea 50 pounds pea, and 
for the diameters of the openings in safety valve seats 
from one to six inches in diameter. Each amount in 
the scale expresses the pounds and thousandths of a 
pound pressure to the square inch in steam, as the load 
on the safety valve for every notch that of a pea of 50 
pounds will produce when moved on ike long end of 
the beam. 

Rule for finding the pressure of steam in a boiler 
by the load on the safety valve : First — Take the di- 
ameter of the opening in the safety valve seat immedi- 
ate below the level in which the valve seats itself. 
Next find the weight in pounds of the safety valve pea, 
which, for example, we will suppose weighs 50 pounds, 
and the opening in the valve seat to be 4 inches in di- 
ameter. Our first operation in figures then, is to 
square the diameter of this opening, or to multiply it 
by itself. Thus, the diameter being 4 inches, 4 times 
4 make 16, which is the square of the diameter sought. 
.Next, in order to find the superficial contents in the 



148 THE PRACTICAL ENGINEER. 

seat, or its area, the decimals .7854 are employed, 

which are to be multiplied by the square of the diam- 

ter of the opening in the seat, which square was found 

to be 16. Out of the product arising of the decimals, 

by the square of the diameter, four right hand figures 

must be pointed off as decimals, and the figures to the 

left of the point in the product will express the whole 

number of square inches contained in the opening, and 

the decimals will express the ten thousandths of a 

square inch, which will be found as follows : 

Rule — Multiply the square of the diameter by 

^8754, and the product will be the area: 

Decimal, .7854 

Square of 4 16 

47124 

7854 



12.5664 

Or multiply the square of the circumference by 
,09958, and the product will be the area. 

Example. — What is the area of a circle whose diam- 
eter is 5 ? 

Decimal, .78:4 
Square of 5 25 



39270 

15708 

19.6350 



THE PRACTICAL ENGINEER. 149 

The product of the multiplication just performed in 
example first, gives 12.5664 as the answer, then hav- 
ing pointed off the four right hand figures according to 
previous instructions, we have 12 inches and .5664 ten 
thousandths of an inch as the area of a circle or open- 
ing of 4 inches diameter. The first left hand decimal 
figure .5 in the product represents tenths of a square 
inch, and the two left hand figures '56 represents hun- 
dredths, or .56 hundreths of a square inch, and the 
three left hand figures denote thousandths, or .566 
thousandths of a square inch, and the whole four deci- 
mals express, as before stated, the ten thousandths of 
a square inch, so that we have an area of 12 inches 
and 5 tenths, or 12 inches and 56 hundredths, or 12 
inches and 566 thousandths, or 12 inches and 5664 
ten thousandths. 

This explanation is essential to a clear understand- 
ing of the principle involved in the calculation of areas 
of circles. It is necessary, also, that the nature of 
decimals be understood : 5 tenths therefore is equiva- 
lent to one half, two-tenths are equal to one-fifth, 
four- tenths are equal two-fifths, six-tenths are equal to 
three-fifths, eight-tenths are equal to four-fifths, and 
ten-tenths are equal to a whole number. It must be 
understood also that not only ten-tenths make a whole 
amount, but one hundred hundredths, or one thousand 

thousandths, or ten thousand ten thousandths, are 
13* 



150 THE PRACTICAL ENGINEER. 

equal in value and equivalent to a whole ; and that .5 
(five-tenths,) .50 (flfty-hundredths,) or .500 (five hun- 
hundred thousandths,) and .f 000 (five thousand ten 
thousandths,) are equivalent to one-half of a whole. 
So, also, .56, the two left hand figures in the above 
example expresses that the area 12.5664 contain 12 
inches and 6 hundredths more than 50 hundredths, or 
one-half of a square inch ; so, also, there are 66 thous- 
andths in .566 more than a half inch, and in .5664 
there are 664 ten thousandths of an inch more than 
half a square inch. 

We will now find out by the load of a 50 pounds pea 
on the safety valve lever, the pressure of steam on the 
boiler for every notch on the lever, the opening to 
be covered by the safetv valve 12.6 square inches, and 
for all practical purposes it is unnececessary to con- 
sider fractions of a less denomination than one-tenth 
in what remains to be done to complete the operations 
on hand. With this understanding as a guide for fu- 
ture operations, our next object will be to take into 
view the proposed amount of weight intended as a load 
on the safety valve. We have supposed the weight to 
be 50 pounds, and the opening in the safety valve seat 
to contain 12.5 square inches, which when the weight 
is placed on the valve covering the opening will require 
a pressure of steam on the boilers equal to 4 pounds to 
each square inch to overcome the load, which will ap- 



THE PRACTICAL ENGINEER. 151 

pear evident when we consider that the safety valve 
covers an opening of 12J square inches, and that 12f 
times 4 make 50. 

Therefore every four pounds of 50 pea is the load 
on each square inch of 12 inches of the opening — -ma^ 
king 48 pounds — and the remaining 21 pounds of the 
50 pounds pea, being the half of 4 pounds, is the load 
on the remaining j- inch of the opening of 12.5 area. 
The principle herein involved should be thoroughly un« 
derstood by repeated revisions of the subject until it is 
well impressed on the mind. In order to arrive at a 
result by figures that we have just produced by mental 
calculation, it will only be necessary to divide 50, the 
weight of the pea, into pounds, by 12.5, the superficial 
contents of the opening in inches. This result will be 
produced by first reducing the. area, 12.5, and weight, 
50, to tenths by multiplying each separately by ten, 
thus — -example ; 

12.5 50 

10 10 

125. 500 

The reason for multiplying the area in inches, and 
weight in pounds by 10, is because the area contains 
fractional parts, whilst the weight of the pea is in 
whole numbers, and because it is necessary to preserve 
their equality oF value in fractional parts in calculat- 
ing that existed before having been reduced to frac- 



152 THE PRACTICAL ENGINEER* 

tions ; and when we divide 500 by 125, the quotient 
will give the steam pressure in the boiler in pounds to 
the square inch, for one notch on the beam of a safety 
valve covering an opening of 125 square inches which 
beam carries a weight of 50 pounds, we proceed in fig- 
ures as follows — example : 

125)500 (4 quotient, 
500 

In the last example we find the quotient to be 4, 
then the product arising from the multiplication of the 
pressure for one notch by any number of notches on 
the beam, will give the steam pressure in the boiler 
when the pea hangs in the notch for the number com- 
puted. Suppose for example, that at 4 pounds to the 
notch, it be required to find the pressure of steam for 
9 notches of the 50 pounds pea on the beam, the mul- 
tiplication of one by the other would give 36 pounds to 
the inch as the pressure of steam, and in the same 
manner the pressure of steam for any number of 
notches may be found. 

For philosophical or experimental purposes, when 
the pressure of steam in a boiler is to be determined 
with nicety and precission, recourse must be had to 
scale 4 and 5, which scales are calculated with mathe- 
matical accuracy : scale 4 giving the steam pressure 
for 1 notch, and for any diameter or opening between 
1 and 6 inches of a safety valve carrying on a beam of 



THE PRACTICAL ENGINEER. 153 

a pea of 50 pounds weight, and scale 5 contains the 
pressure of steam for one notch in the same manner 
for a safety valve carrying a pea 100 pounds weight 
on the beam. From the preceeding explanations and 
examples, it will be obvious the product arising from 
the multiplication of any pressure found on scale 4 by 
any number of notches on the beam, will give the 
presrure of steam in the boiler in pounds and in thous- 
andths of a pound to the square inch. However, pre- 
caution must be taken to point off three right hand 
figures in the product for decimals, as the pressure in 
the scales contain three decimals. 

The same course is to be pursued with reference to 
scale 5, except it must be observed the pressure in 
scale 5 contains 4 decimal places, and that the right 
hand figures in the product of every multiplication 
must be pointed off, and the result will give the pres- 
sure in pounds and ten thousandths of pounds to the 
square inch of steam in the boiler for a safety valve 
loaded with a pea on the beam weighing 100 pounds. 

Note. — When 25 or 75 pounds, or any other pressure of steam, great- 
er or less, is desirable, by adopting a method of calculation based upon 
these principles, the load on the safety valve may be easily adjusted to 
produce any required pressure of steam on the boilers. 



154 WALLACE'S VERTICAL STEAM BOILER. 



JOHN WALLACE'S VERTICAL 

STEAM BOILER. 

This boiler having for a long time engaged the at- 
tention of the inventor, (who has applied for Letters 
Patent to secure his invention,) is now before the pub- 
lic. It has been thoroughly tested, and, we think, 
proved to be superior to all the other boilers now in 
use. It will raise steam faster than any other boiler, 
consume less fuel, and is less liable to explosion. It is 
so constructed that with a full head of steam, and 
while the engine is in motion, the sediment can be dis- 
lodged, and then discharged through the mud valve, 
thus relieving it from the the danger of choking up 
with mud and sediment, to which small flue and tub- 
ular boilers are so liable. 

It is cylindrical and easily transported. It requires 
no fire front, no boiler stands, and no furnace of brick 
or mason work, (the furnace being entirely inside of 
the boiler,) and not over one third the grate bars 
requisite for ordinary boilers. 

The furnace in this boiler being entirely surrounded 
with water, there is but little danger from fire, and in- 
surance companies have insured factories where these 
boilers have been used, for 25 to 40 per cent less than 



Pa.tfe.T55. 



TJ]ori4ht Boiloir with jj lJpTi^Iit sliaft in 



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Wallace's vertical steam boiler. 155 

they would do when the common boilers were used. 
The decreased consumption of fuel (over 38 per cent) 
to produce a given aimount of steam, is a matter of no 
small importance in any country, but it becomes a sub- 
ject of the first consideration in sections where fuel is 
dear. The vertical boiler occupies about one-tenth 
only of the ground space required for a horrkonta! 
boiler, and when We consider this fact in connection 
with the decreased room required for storage of fuel/ 
and ashes,- the economy of space becomes a matter of 
great importance* and particularly so in large towns 
and cities. 

One of'these boilers can be seen in the printing es- 
tablishment of Kennedy & Brother, near Pittsburgh,- 
one at Wheelock, Church k Co/s Factory, Bedford,- 
6uyahoga County, 0, another at the Hillsboro' and 
Cincinnatti Railroad,- 10 miles east of Cincinnatti, and 
Others will be put in operation in a few days. 

We annex the following certificates from persons- 
using these boilers i 

JBeMord, 0., June 28, 1853. 

ff. W< Wallace^ Mq< ; Dear Sir— We have been 
Using the Vertical Boiler you made for us, for the last' 
ten da^s, and find that it works extremely well. We 
Use shavings, saw-dust, and in fact anything at all for 
fuel, and find no difficulty in raising steam with any 
kind of fuel. In fact, the more we use it, we feel bet- 



156 Wallace's vertical steam boiler, 

ter satisfied that it is superior to the old horizontal 
boiler, and feel safe in recommending it to any who 
want a boiler that requires little fuel and less atten- 
tion. We have tried it with cord wood, and find that 
it requires } of a cord of wood to keep up a hot fire for 
one day. Respectfully your friends, 

WHEELOCK, CHURCH & CO. 

Pittsburgh, Aug. 3, 1853. 
W. W. Wallace : Dear Sir — We have now in use 
in our Printing Establishment, Manchester, one of 
your new Yertical Boilers, for which you have applied 
for letters patent. It gives entire satisfaction, and 
we cheer fully recommend it as being more safe, eco- 
nonical and useful, than any other boiler with which 
we are acquainted. Our machinery is kept running 
constantly, and we do not consume more than three 
bushels of coal per day. KENNEDY & BRO., 
Publishers "Kennedys' Bank Note Review," 3dst. 

Pittsburgh, July 16, 1853. 

W. W. Wallace : Dear Sir— I have used tho Ver- 
tical Boiler I bought of you for over three months, and 
am well satisfied with it. It occupies less space, con- 
sumes less fuel, and raises steam faster than any other 
boiler that I am acquainted with. I would confidently 
recommend them to those who want a first rate boiler. 

JOHN D. DAVIS, JR. 

All orders promptly attended to. 

W. W. WALLACE, 
319 Liberty-st., Pittsburgh. 



157 



MISCELLANEOUS. 



Steamboat Disasters. — Investigations made by a 
Congressional Committee, show the following loss of 
property and life on the rivers and lakes of the Uni- 
ted States, in each of the following four years : 

Amount of property Number of 
Years. destroyed. lives lost. 

1848, 420,512 $5 

1849, 368,171 84 

1850, 558,826 395 

1851, 730,537 79 



Total 4 years, #2,078,046 563 

The number of lives lost in 1850 was mainly occa- 
sioned by the explosion of boilers on board two steam- 
boats, and the burning of a third, crowded with emi- 
grant passengers. 



Life Boat Steamers. — A new plan for building 
steamers has been brought out in England, and an ex- 
perimental boat built to run from London to Boulogne. 
This boat is 235 feet long, 20 feet beam, of 250 tons 
burden, and has an engine of 50 horse power. The 



158 MISCELLANEOUS. 

bow and stem are filled with fixed air, like a life boat. 
If it meets the expectations of the inventor and buil- 
ders, two immense vessels of 10,000 tons and 100 horse 
power will at once be built on the same plan; they 
will run from London to the east Indies in thirty days, 
without stopping on the way. 



Gardner's Eock Drill. — G-. A. Gardner, of Bos- 
ton, has obtained, in 1852, a patent for a Rock Drill, 
designed for drilling blasts and wedge holes in rock, 
which we think worthy special notice. 

It drills horrizontally as well as perpendicularly, or 
at any angle. The drill is drawn back six inches by 
cams rotated in a shaft, and projected against the rock 
by an india rubber spring, similar to the rubber car 
springs, repeating the blow from 120 to 150 times per 
minute. The patentee guarantees the machine to drill 
five lineal feet of 3 to 6 inch blast holes per hour, or 
fifty feet per ten hours in granite. The rate of ad- 
vance when actually working, is J to 2 inches per min- 
ute. In soft rock the advance is much faster. In 
limestone or mica slate, the rate of 3 to 4 inches per 
minute can be attained. 

This machine is peculiarly adapted to tunneling — 4 
to 6 drills being combined in one machine, being equal 
to 150 or more men working at one section. 



MISCELLANEOUS. 159 

Navies of the World. — Great Britain has 136 
vessels afloat, or, in ordinary or building, carrying 
17,681 guns ; France has 346, carrying 8,928 guns ; 
Russia has 179 afloat, carrying 5,896 guns ; Holland 
has 134, carrying 2,600 guns ; the United States has 
77, carrying 2,245 guns. 



DiviNa Boat. — A new diving boat is now exhibiting 
at Cherbourg, France. Dr. Payerne is the inventor, 
and he has discovered means to descend to the bottom 
of the sea, and to remain there with a body of opera- 
tives as long as he pleases, replaceing, by chemical 
means, the oxygen absorbed. He also found a mode 
of directing the boat under water, by steam, as if it 
were on the surface. He engages to reach the English 
coast from any harbor in France. This invention is 
promised the patronage of the Prince President. . 



Whirlpools and Whirlwinds. — If in the bottom 
of a pond, or other reservoir of water there be an 
aperture through which the fluid is allowed to flow, 
there will be formed, immediately above the outlet, a 
whirling vorteXj which is called a "whirlpool." It is 
formed by the currents from opposite directions meet- 
ing each other at the aperture ; the meeting of these 
currents gives rise to a circular motion, which extends 



160 MISCELLANEOUS 

to some distance ; this motion imparts to the water a 
centrifugal force, by which it is thrown from the cen- 
ter, leaving a funnel-shaped hole from the surface to 
the outlet. The Maelstrom, a large whirlpool in the 
ocean, off the coast of Norway, has a vortex sufficient 
to swallow up the largest ships. 

Precisely analagous to the whirlpool is the "whirl- 
wind ;" the heated air at any portion of the earth's 
surface being caused to rise by the pressure of the 
surrounding colder and heavier air, the meeting cur- 
rents produce a whirlwind. Whirlwinds are also fre- 
quently produced by contrary winds. The partial 
vacuum, caused by the ascending whirl, is commonly 
filled with dust, leaves, straws, and other light bodies, 
which it takes up in its course. It is sometimes suffi- 
ciently powerful to uproot trees and uproof houses. 
If the current of air from any rarticular quarter be of 
greater force than the other, the whirlwind then 
acquires a progessive as well as a rotary motion. 

Note. — Page 145 and 153, inclusive, alludes to a table, (gotten up 
expressly for the uneducated engineer,) embracing all the different sizes 
of safety valves, from one to six inches, including all the one-eighth 
inches between one and six inches, having two separate tables, one for 
100 pounds pea, and one for 150 pounds pea, and a third table showing 
the different degrees of heat at the various numbers of pounds to which 
the steam may be carried. This table having been lost or mislaid, and 
as it would require much time and labor to get up another, the author 
deemed it best not to delay the publication of the present volume, and 
offers, as a substitute, a smaller one. The sizes of valves in the substitute 
will be from 3 inches up to 6 inches, including the one-fourth inches. 
The second volume of the work will contain the large table. 

The Author. 

W, W. J. WALLACE'S ENGINE ESTABLISHMENT, 
319 and 321 Liberty Street, Pittsburgh, Pa. Steam Engines for Saw and Flour 
Mills, generally on hand. Orders promptly attended to. W. W. WALLACE. 

Il 17 Ftb.1860 L] 

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